This is zsh.info, produced by makeinfo version 4.8 from ./zsh.texi. INFO-DIR-SECTION Utilities START-INFO-DIR-ENTRY * ZSH: (zsh). The Z Shell Manual. END-INFO-DIR-ENTRY  File: zsh.info, Node: Completion Functions, Next: Completion System Variables, Prev: Bindable Commands, Up: Completion System 20.6 Utility Functions ====================== Descriptions follow for utility functions that may be useful when writing completion functions. If functions are installed in subdirectories, most of these reside in the Base subdirectory. Like the example functions for commands in the distribution, the utility functions generating matches all follow the convention of returning status zero if they generated completions and non-zero if no matching completions could be added. _absolute_command_paths This function completes external commands as absolute paths (unlike _command_names -e which completes their basenames). It takes no arguments. _all_labels [ -x ] [ -12VJ ] TAG NAME DESCR [ COMMAND ARG ... ] This is a convenient interface to the _next_label function below, implementing the loop shown in the _next_label example. The COMMAND and its arguments are called to generate the matches. The options stored in the parameter NAME will automatically be inserted into the ARGs passed to the COMMAND. Normally, they are put directly after the COMMAND, but if one of the ARGs is a single hyphen, they are inserted directly before that. If the hyphen is the last argument, it will be removed from the argument list before the COMMAND is called. This allows _all_labels to be used in almost all cases where the matches can be generated by a single call to the compadd builtin command or by a call to one of the utility functions. For example: local expl ... if _requested foo; then ... _all_labels foo expl '...' compadd ... - $matches fi Will complete the strings from the matches parameter, using compadd with additional options which will take precedence over those generated by _all_labels. _alternative [ -O NAME ] [ -C NAME ] SPEC ... This function is useful in simple cases where multiple tags are available. Essentially it implements a loop like the one described for the _tags function below. The tags to use and the action to perform if a tag is requested are described using the SPECs which are of the form: `TAG:DESCR:ACTION'. The TAGs are offered using _tags and if the tag is requested, the ACTION is executed with the given description DESCR. The ACTIONs are those accepted by the _arguments function (described below), excluding the `->STATE' and `=...' forms. For example, the ACTION may be a simple function call: _alternative \ 'users:user:_users' \ 'hosts:host:_hosts' offers usernames and hostnames as possible matches, generated by the _users and _hosts functions respectively. Like _arguments, this function uses _all_labels to execute the actions, which will loop over all sets of tags. Special handling is only required if there is an additional valid tag, for example inside a function called from _alternative. The option `-O NAME' is used in the same way as by the _arguments function. In other words, the elements of the NAME array will be passed to compadd when executing an action. Like _tags this function supports the -C option to give a different name for the argument context field. _arguments [ -nswWCRS ] [ -A PAT ] [ -O NAME ] [ -M MATCHSPEC ] [ : ] SPEC ... _arguments [ OPT ... ] -- [ -l ] [ -i PATS ] [ -s PAIR ] [ HELPSPEC ...] This function can be used to give a complete specification for completion for a command whose arguments follow standard UNIX option and argument conventions. _Options Overview_ Options to _arguments itself must be in separate words, i.e. -s -w, not -sw. The options are followed by SPECs that describe options and arguments of the analyzed command. To avoid ambiguity, all options to _arguments itself may be separated from the SPEC forms by a single colon. The `--' form is used to intuit SPEC forms from the help output of the command being analyzed, and is described in detail below. The OPTS for the `--' form are otherwise the same options as the first form. Note that `-s' following `--' has a distinct meaning from `-s' preceding `--', and both may appear. The option switches -s, -S, -A, -w, and -W affect how _arguments parses the analyzed command line's options. These switches are useful for commands with standard argument parsing. The options of _arguments have the following meanings: -n With this option, _arguments sets the parameter NORMARG to the position of the first normal argument in the $words array, i.e. the position after the end of the options. If that argument has not been reached, NORMARG is set to -1. The caller should declare `integer NORMARG' if the -n option is passed; otherwise the parameter is not used. -s Enable _option stacking_ for single-letter options, whereby multiple single-letter options may be combined into a single word. For example, the two options `-x' and `-y' may be combined into a single word `-xy'. By default, every word corresponds to a single option name (`-xy' is a single option named `xy'). Options beginning with a single hyphen or plus sign are eligible for stacking; words beginning with two hyphens are not. Note that -s after -- has a different meaning, which is documented in the segment entitled `Deriving SPEC forms from the help output'. -w In combination with -s, allow option stacking even if one or more of the options take arguments. For example, if -x takes an argument, with no -s, `-xy' is considered as a single (unhandled) option; with -s, -xy is an option with the argument `y'; with both -s and -w, -xy is the option -x and the option -y with arguments to -x (and to -y, if it takes arguments) still to come in subsequent words. -W This option takes -w a stage further: it is possible to complete single-letter options even after an argument that occurs in the same word. However, it depends on the action performed whether options will really be completed at this point. For more control, use a utility function like _guard as part of the action. -C Modify the curcontext parameter for an action of the form `->STATE'. This is discussed in detail below. -R Return status 300 instead of zero when a $state is to be handled, in the `->STRING' syntax. -S Do not complete options after a `--' appearing on the line, and ignore the `--'. For example, with -S, in the line foobar -x -- -y the `-x' is considered an option, the `-y' is considered an argument, and the `--' is considered to be neither. -A PAT Do not complete options after the first non-option argument on the line. PAT is a pattern matching all strings which are not to be taken as arguments. For example, to make _arguments stop completing options after the first normal argument, but ignoring all strings starting with a hyphen even if they are not described by one of the OPTSPECs, the form is `-A "-*"'. -O NAME Pass the elements of the array NAME as arguments to functions called to execute ACTIONs. This is discussed in detail below. -M MATCHSPEC Use the match specification MATCHSPEC for completing option names and values. The default MATCHSPEC allows partial word completion after `_' and `-', such as completing `-f-b' to `-foo-bar'. The default MATCHSPEC is: r:|[_-]=* r:|=* _SPECs: overview_ Each of the following forms is a SPEC describing individual sets of options or arguments on the command line being analyzed. N:MESSAGE:ACTION N::MESSAGE:ACTION This describes the N'th normal argument. The MESSAGE will be printed above the matches generated and the ACTION indicates what can be completed in this position (see below). If there are two colons before the MESSAGE the argument is optional. If the MESSAGE contains only white space, nothing will be printed above the matches unless the action adds an explanation string itself. :MESSAGE:ACTION ::MESSAGE:ACTION Similar, but describes the _next_ argument, whatever number that happens to be. If all arguments are specified in this form in the correct order the numbers are unnecessary. *:MESSAGE:ACTION *::MESSAGE:ACTION *:::MESSAGE:ACTION This describes how arguments (usually non-option arguments, those not beginning with - or +) are to be completed when neither of the first two forms was provided. Any number of arguments can be completed in this fashion. With two colons before the MESSAGE, the words special array and the CURRENT special parameter are modified to refer only to the normal arguments when the ACTION is executed or evaluated. With three colons before the MESSAGE they are modified to refer only to the normal arguments covered by this description. OPTSPEC OPTSPEC:... This describes an option. The colon indicates handling for one or more arguments to the option; if it is not present, the option is assumed to take no arguments. The following forms are available for the initial OPTSPEC, whether or not the option has arguments. *OPTSPEC Here OPTSPEC is one of the remaining forms below. This indicates the following OPTSPEC may be repeated. Otherwise if the corresponding option is already present on the command line to the left of the cursor it will not be offered again. -OPTNAME +OPTNAME In the simplest form the OPTSPEC is just the option name beginning with a minus or a plus sign, such as `-foo'. The first argument for the option (if any) must follow as a _separate_ word directly after the option. Either of `-+OPTNAME' and `+-OPTNAME' can be used to specify that -OPTNAME and +OPTNAME are both valid. In all the remaining forms, the leading `-' may be replaced by or paired with `+' in this way. -OPTNAME- The first argument of the option must come directly after the option name _in the same word_. For example, `-foo-:...' specifies that the completed option and argument will look like `-fooARG'. -OPTNAME+ The first argument may appear immediately after OPTNAME in the same word, or may appear as a separate word after the option. For example, `-foo+:...' specifies that the completed option and argument will look like either `-fooARG' or `-foo ARG'. -OPTNAME= The argument may appear as the next word, or in same word as the option name provided that it is separated from it by an equals sign, for example `-foo=ARG' or `-foo ARG'. -OPTNAME=- The argument to the option must appear after an equals sign in the same word, and may not be given in the next argument. OPTSPEC[EXPLANATION] An explanation string may be appended to any of the preceding forms of OPTSPEC by enclosing it in brackets, as in `-q[query operation]'. The verbose style is used to decide whether the explanation strings are displayed with the option in a completion listing. If no bracketed explanation string is given but the auto-description style is set and only one argument is described for this OPTSPEC, the value of the style is displayed, with any appearance of the sequence `%d' in it replaced by the MESSAGE of the first OPTARG that follows the OPTSPEC; see below. It is possible for options with a literal `+' or `=' to appear, but that character must be quoted, for example `-\+'. Each OPTARG following an OPTSPEC must take one of the following forms: :MESSAGE:ACTION ::MESSAGE:ACTION An argument to the option; MESSAGE and ACTION are treated as for ordinary arguments. In the first form, the argument is mandatory, and in the second form it is optional. This group may be repeated for options which take multiple arguments. In other words, :MESSAGE1:ACTION1:MESSAGE2:ACTION2 specifies that the option takes two arguments. :*PATTERN:MESSAGE:ACTION :*PATTERN::MESSAGE:ACTION :*PATTERN:::MESSAGE:ACTION This describes multiple arguments. Only the last OPTARG for an option taking multiple arguments may be given in this form. If the PATTERN is empty (i.e. :*:), all the remaining words on the line are to be completed as described by the ACTION; otherwise, all the words up to and including a word matching the PATTERN are to be completed using the ACTION. Multiple colons are treated as for the `*:...' forms for ordinary arguments: when the MESSAGE is preceded by two colons, the words special array and the CURRENT special parameter are modified during the execution or evaluation of the ACTION to refer only to the words after the option. When preceded by three colons, they are modified to refer only to the words covered by this description. Any literal colon in an OPTNAME, MESSAGE, or ACTION must be preceded by a backslash, `\:'. Each of the forms above may be preceded by a list in parentheses of option names and argument numbers. If the given option is on the command line, the options and arguments indicated in parentheses will not be offered. For example, `(-two -three 1)-one:...' completes the option `-one'; if this appears on the command line, the options -two and -three and the first ordinary argument will not be completed after it. `(-foo):...' specifies an ordinary argument completion; -foo will not be completed if that argument is already present. Other items may appear in the list of excluded options to indicate various other items that should not be applied when the current specification is matched: a single star (*) for the rest arguments (i.e. a specification of the form `*:...'); a colon (:) for all normal (non-option-) arguments; and a hyphen (-) for all options. For example, if `(*)' appears before an option and the option appears on the command line, the list of remaining arguments (those shown in the above table beginning with `*:') will not be completed. To aid in reuse of specifications, it is possible to precede any of the forms above with `!'; then the form will no longer be completed, although if the option or argument appears on the command line they will be skipped as normal. The main use for this is when the arguments are given by an array, and _arguments is called repeatedly for more specific contexts: on the first call `_arguments $global_options' is used, and on subsequent calls `_arguments !$^global_options'. _SPECs: actions_ In each of the forms above the ACTION determines how completions should be generated. Except for the `->STRING' form below, the ACTION will be executed by calling the _all_labels function to process all tag labels. No special handling of tags is needed unless a function call introduces a new one. The functions called to execute ACTIONs will be called with the elements of the array named by the `-O NAME' option as arguments. This can be used, for example, to pass the same set of options for the compadd builtin to all ACTIONs. The forms for ACTION are as follows. (single unquoted space) This is useful where an argument is required but it is not possible or desirable to generate matches for it. The MESSAGE will be displayed but no completions listed. Note that even in this case the colon at the end of the MESSAGE is needed; it may only be omitted when neither a MESSAGE nor an ACTION is given. (ITEM1 ITEM2 ...) One of a list of possible matches, for example: :foo:(foo bar baz) ((ITEM1\:DESC1 ...)) Similar to the above, but with descriptions for each possible match. Note the backslash before the colon. For example, :foo:((a\:bar b\:baz)) The matches will be listed together with their descriptions if the description style is set with the values tag in the context. ->STRING In this form, _arguments processes the arguments and options and then returns control to the calling function with parameters set to indicate the state of processing; the calling function then makes its own arrangements for generating completions. For example, functions that implement a state machine can use this type of action. Where _arguments encounters ACTION in the `->STRING' format, it will strip all leading and trailing whitespace from STRING and set the array state to the set of all STRINGs for which an action is to be performed. The elements of the array state_descr are assigned the corresponding MESSAGE field from each OPTARG containing such an ACTION. By default and in common with all other well behaved completion functions, _arguments returns status zero if it was able to add matches and non-zero otherwise. However, if the -R option is given, _arguments will instead return a status of 300 to indicate that $state is to be handled. In addition to $state and $state_descr, _arguments also sets the global parameters `context', `line' and `opt_args' as described below, and does not reset any changes made to the special parameters such as PREFIX and words. This gives the calling function the choice of resetting these parameters or propagating changes in them. A function calling _arguments with at least one action containing a `->STRING' must therefore declare appropriate local parameters: local context state state_descr line typeset -A opt_args to prevent _arguments from altering the global environment. {EVAL-STRING} A string in braces is evaluated as shell code to generate matches. If the EVAL-STRING itself does not begin with an opening parenthesis or brace it is split into separate words before execution. = ACTION If the ACTION starts with `= ' (an equals sign followed by a space), _arguments will insert the contents of the ARGUMENT field of the current context as the new first element in the words special array and increment the value of the CURRENT special parameter. This has the effect of inserting a dummy word onto the completion command line while not changing the point at which completion is taking place. This is most useful with one of the specifiers that restrict the words on the command line on which the ACTION is to operate (the two- and three-colon forms above). One particular use is when an ACTION itself causes _arguments on a restricted range; it is necessary to use this trick to insert an appropriate command name into the range for the second call to _arguments to be able to parse the line. WORD... WORD... This covers all forms other than those above. If the ACTION starts with a space, the remaining list of words will be invoked unchanged. Otherwise it will be invoked with some extra strings placed after the first word; these are to be passed down as options to the compadd builtin. They ensure that the state specified by _arguments, in particular the descriptions of options and arguments, is correctly passed to the completion command. These additional arguments are taken from the array parameter `expl'; this will be set up before executing the ACTION and hence may be referred to inside it, typically in an expansion of the form `$expl[@]' which preserves empty elements of the array. During the performance of the action the array `line' will be set to the normal arguments from the command line, i.e. the words from the command line after the command name excluding all options and their arguments. Options are stored in the associative array `opt_args' with option names as keys and their arguments as the values. For options that have more than one argument these are given as one string, separated by colons. All colons and backslashes in the original arguments are preceded with backslashes. The parameter `context' is set when returning to the calling function to perform an action of the form `->STRING'. It is set to an array of elements corresponding to the elements of $state. Each element is a suitable name for the argument field of the context: either a string of the form `option-OPT-N' for the N'th argument of the option -OPT, or a string of the form `argument-N' for the N'th argument. For `rest' arguments, that is those in the list at the end not handled by position, N is the string `rest'. For example, when completing the argument of the -o option, the name is `option-o-1', while for the second normal (non-option-) argument it is `argument-2'. Furthermore, during the evaluation of the ACTION the context name in the curcontext parameter is altered to append the same string that is stored in the context parameter. The option -C tells _arguments to modify the curcontext parameter for an action of the form `->STATE'. This is the standard parameter used to keep track of the current context. Here it (and not the context array) should be made local to the calling function to avoid passing back the modified value and should be initialised to the current value at the start of the function: local curcontext="$curcontext" This is useful where it is not possible for multiple states to be valid together. _Grouping Options_ Options can be grouped to simplify exclusion lists. A group is introduced with `+' followed by a name for the group in the subsequent word. Whole groups can then be referenced in an exclusion list or a group name can be used to disambiguate between two forms of the same option. For example: _arguments \ '(group2--x)-a' \ + group1 \ -m \ '(group2)-n' \ + group2 \ -x -y If the name of a group is specified in the form `(NAME)' then only one value from that group will ever be completed; more formally, all specifications are mutually exclusive to all other specifications in that group. This is useful for defining options that are aliases for each other. For example: _arguments \ -a -b \ + '(operation)' \ {-c,--compress}'[compress]' \ {-d,--decompress}'[decompress]' \ {-l,--list}'[list]' If an option in a group appears on the command line, it is stored in the associative array `opt_args' with 'GROUP-OPTION' as a key. In the example above, a key `operation-c' is used if the option `-c' is present on the command line. _Specifying Multiple Sets of Arguments_ It is possible to specify multiple sets of options and arguments with the sets separated by single hyphens. This differs from groups in that sets are considered to be mutually exclusive of each other. Specifications before the first set and from any group are common to all sets. For example: _arguments \ -a \ - set1 \ -c \ - set2 \ -d \ ':arg:(x2 y2)' This defines two sets. When the command line contains the option `-c', the `-d' option and the argument will not be considered possible completions. When it contains `-d' or an argument, the option `-c' will not be considered. However, after `-a' both sets will still be considered valid. As for groups, the name of a set may appear in exclusion lists, either alone or preceding a normal option or argument specification. The completion code has to parse the command line separately for each set. This can be slow so sets should only be used when necessary. A useful alternative is often an option specification with rest-arguments (as in `-foo:*:...'); here the option -foo swallows up all remaining arguments as described by the OPTARG definitions. _Deriving SPEC forms from the help output_ The option `--' allows _arguments to work out the names of long options that support the `--help' option which is standard in many GNU commands. The command word is called with the argument `--help' and the output examined for option names. Clearly, it can be dangerous to pass this to commands which may not support this option as the behaviour of the command is unspecified. In addition to options, `_arguments --' will try to deduce the types of arguments available for options when the form `--OPT=VAL' is valid. It is also possible to provide hints by examining the help text of the command and adding HELPSPEC of the form `PATTERN:MESSAGE:ACTION'; note that other _arguments SPEC forms are not used. The PATTERN is matched against the help text for an option, and if it matches the MESSAGE and ACTION are used as for other argument specifiers. The special case of `*:' means both MESSAGE and ACTION are empty, which has the effect of causing options having no description in the help output to be ordered in listings ahead of options that have a description. For example: _arguments -- '*\*:toggle:(yes no)' \ '*=FILE*:file:_files' \ '*=DIR*:directory:_files -/' \ '*=PATH*:directory:_files -/' Here, `yes' and `no' will be completed as the argument of options whose description ends in a star; file names will be completed for options that contain the substring `=FILE' in the description; and directories will be completed for options whose description contains `=DIR' or `=PATH'. The last three are in fact the default and so need not be given explicitly, although it is possible to override the use of these patterns. A typical help text which uses this feature is: -C, --directory=DIR change to directory DIR so that the above specifications will cause directories to be completed after `--directory', though not after `-C'. Note also that _arguments tries to find out automatically if the argument for an option is optional. This can be specified explicitly by doubling the colon before the MESSAGE. If the PATTERN ends in `(-)', this will be removed from the pattern and the ACTION will be used only directly after the `=', not in the next word. This is the behaviour of a normal specification defined with the form `=-'. By default, the command (with the option `-help') is run after resetting all the locale categories (except for LC_CTYPE) to `C'. If the localized help output is known to work, the option `-l' can be specified after the `_arguments --' so that the command is run in the current locale. The `_arguments --' can be followed by the option `-i PATTERNS' to give patterns for options which are not to be completed. The patterns can be given as the name of an array parameter or as a literal list in parentheses. For example, _arguments -- -i \ "(--(en|dis)able-FEATURE*)" will cause completion to ignore the options `--enable-FEATURE' and `--disable-FEATURE' (this example is useful with GNU configure). The `_arguments --' form can also be followed by the option `-s PAIR' to describe option aliases. The PAIR consists of a list of alternating patterns and corresponding replacements, enclosed in parens and quoted so that it forms a single argument word in the _arguments call. For example, some configure-script help output describes options only as `--enable-foo', but the script also accepts the negated form `--disable-foo'. To allow completion of the second form: _arguments -- -s "((#s)--enable- --disable-)" _Miscellaneous notes_ Finally, note that _arguments generally expects to be the primary function handling any completion for which it is used. It may have side effects which change the treatment of any matches added by other functions called after it. To combine _arguments with other functions, those functions should be called either before _arguments, as an ACTION within a SPEC, or in handlers for `->STATE' actions. Here is a more general example of the use of _arguments: _arguments '-l+:left border:' \ '-format:paper size:(letter A4)' \ '*-copy:output file:_files::resolution:(300 600)' \ ':postscript file:_files -g \*.\(ps\|eps\)' \ '*:page number:' This describes three options: `-l', `-format', and `-copy'. The first takes one argument described as `LEFT BORDER' for which no completion will be offered because of the empty action. Its argument may come directly after the `-l' or it may be given as the next word on the line. The `-format' option takes one argument in the next word, described as `PAPER SIZE' for which only the strings `letter' and `A4' will be completed. The `-copy' option may appear more than once on the command line and takes two arguments. The first is mandatory and will be completed as a filename. The second is optional (because of the second colon before the description `RESOLUTION') and will be completed from the strings `300' and `600'. The last two descriptions say what should be completed as arguments. The first describes the first argument as a `POSTSCRIPT FILE' and makes files ending in `ps' or `eps' be completed. The last description gives all other arguments the description `PAGE NUMBERS' but does not offer completions. _cache_invalid CACHE_IDENTIFIER This function returns status zero if the completions cache corresponding to the given cache identifier needs rebuilding. It determines this by looking up the cache-policy style for the current context. This should provide a function name which is run with the full path to the relevant cache file as the only argument. Example: _example_caching_policy () { # rebuild if cache is more than a week old local -a oldp oldp=( "$1"(Nm+7) ) (( $#oldp )) } _call_function RETURN NAME [ ARG ... ] If a function NAME exists, it is called with the arguments ARGs. The RETURN argument gives the name of a parameter in which the return status from the function NAME should be stored; if RETURN is empty or a single hyphen it is ignored. The return status of _call_function itself is zero if the function NAME exists and was called and non-zero otherwise. _call_program [ -l ] [ -p ] TAG STRING ... This function provides a mechanism for the user to override the use of an external command. It looks up the command style with the supplied TAG. If the style is set, its value is used as the command to execute. The STRINGs from the call to _call_program, or from the style if set, are concatenated with spaces between them and the resulting string is evaluated. The return status is the return status of the command called. By default, the command is run in an environment where all the locale categories (except for LC_CTYPE) are reset to `C' by calling the utility function _comp_locale (see below). If the option `-l' is given, the command is run with the current locale. If the option `-p' is supplied it indicates that the command output is influenced by the permissions it is run with. If the gain-privileges style is set to true, _call_program will make use of commands such as sudo, if present on the command-line, to match the permissions to whatever the final command is likely to run under. When looking up the gain-privileges and command styles, the command component of the zstyle context will end with a slash (`/') followed by the command that would be used to gain privileges. _combination [ -s PATTERN ] TAG STYLE SPEC ... FIELD OPTS ... This function is used to complete combinations of values, for example pairs of hostnames and usernames. The STYLE argument gives the style which defines the pairs; it is looked up in a context with the TAG specified. The style name consists of field names separated by hyphens, for example `users-hosts-ports'. For each field for a value is already known, a SPEC of the form `FIELD=PATTERN' is given. For example, if the command line so far specifies a user `pws', the argument `users=pws' should appear. The next argument with no equals sign is taken as the name of the field for which completions should be generated (presumably not one of the FIELDs for which the value is known). The matches generated will be taken from the value of the style. These should contain the possible values for the combinations in the appropriate order (users, hosts, ports in the example above). The values for the different fields are separated by colons. This can be altered with the option -s to _combination which specifies a pattern. Typically this is a character class, as for example `-s "[:@]"' in the case of the users-hosts style. Each `FIELD=PATTERN' specification restricts the completions which apply to elements of the style with appropriately matching fields. If no style with the given name is defined for the given tag, or if none of the strings in style's value match, but a function name of the required field preceded by an underscore is defined, that function will be called to generate the matches. For example, if there is no `users-hosts-ports' or no matching hostname when a host is required, the function `_hosts' will automatically be called. If the same name is used for more than one field, in both the `FIELD=PATTERN' and the argument that gives the name of the field to be completed, the number of the field (starting with one) may be given after the fieldname, separated from it by a colon. All arguments after the required field name are passed to compadd when generating matches from the style value, or to the functions for the fields if they are called. _command_names [ -e | - ] This function completes words that are valid at command position: names of aliases, builtins, hashed commands, functions, and so on. With the -e flag, only hashed commands are completed. The - flag is ignored. _comp_locale This function resets all the locale categories other than LC_CTYPE to `C' so that the output from external commands can be easily analyzed by the completion system. LC_CTYPE retains the current value (taking LC_ALL and LANG into account), ensuring that non-ASCII characters in file names are still handled properly. This function should normally be run only in a subshell, because the new locale is exported to the environment. Typical usage would be `$(_comp_locale; COMMAND ...)'. _completers [ -p ] This function completes names of completers. -p Include the leading underscore (`_') in the matches. _describe [-12JVx] [ -oO | -t TAG ] DESCR NAME1 [ NAME2 ] [ OPT ... ] [ -- NAME1 [ NAME2 ] [ OPT ... ] ... ] This function associates completions with descriptions. Multiple groups separated by -- can be supplied, potentially with different completion options OPTs. The DESCR is taken as a string to display above the matches if the format style for the descriptions tag is set. This is followed by one or two names of arrays followed by options to pass to compadd. The array NAME1 contains the possible completions with their descriptions in the form `COMPLETION:DESCRIPTION'. Any literal colons in COMPLETION must be quoted with a backslash. If a NAME2 is given, it should have the same number of elements as NAME1; in this case the corresponding elements are added as possible completions instead of the COMPLETION strings from NAME1. The completion list will retain the descriptions from NAME1. Finally, a set of completion options can appear. If the option `-o' appears before the first argument, the matches added will be treated as names of command options (N.B. not shell options), typically following a `-', `--' or `+' on the command line. In this case _describe uses the prefix-hidden, prefix-needed and verbose styles to find out if the strings should be added as completions and if the descriptions should be shown. Without the `-o' option, only the verbose style is used to decide how descriptions are shown. If `-O' is used instead of `-o', command options are completed as above but _describe will not handle the prefix-needed style. With the -t option a TAG can be specified. The default is `values' or, if the -o option is given, `options'. The options -1, -2, -J, -V, -x are passed to _next_label. If selected by the list-grouped style, strings with the same description will appear together in the list. _describe uses the _all_labels function to generate the matches, so it does not need to appear inside a loop over tag labels. _description [ -x ] [ -12VJ ] TAG NAME DESCR [ SPEC ... ] This function is not to be confused with the previous one; it is used as a helper function for creating options to compadd. It is buried inside many of the higher level completion functions and so often does not need to be called directly. The styles listed below are tested in the current context using the given TAG. The resulting options for compadd are put into the array named NAME (this is traditionally `expl', but this convention is not enforced). The description for the corresponding set of matches is passed to the function in DESCR. The styles tested are: format, hidden, matcher, ignore-line, ignored-patterns, group-name and sort. The format style is first tested for the given TAG and then for the descriptions tag if no value was found, while the remainder are only tested for the tag given as the first argument. The function also calls _setup which tests some more styles. The string returned by the format style (if any) will be modified so that the sequence `%d' is replaced by the DESCR given as the third argument without any leading or trailing white space. If, after removing the white space, the DESCR is the empty string, the format style will not be used and the options put into the NAME array will not contain an explanation string to be displayed above the matches. If _description is called with more than three arguments, the additional SPECs should be of the form `CHAR:STR'. These supply escape sequence replacements for the format style: every appearance of `%CHAR' will be replaced by STRING. If the -x option is given, the description will be passed to compadd using the -x option instead of the default -X. This means that the description will be displayed even if there are no corresponding matches. The options placed in the array NAME take account of the group-name style, so matches are placed in a separate group where necessary. The group normally has its elements sorted (by passing the option -J to compadd), but if an option starting with `-V', `-J', `-1', or `-2' is passed to _description, that option will be included in the array. Hence it is possible for the completion group to be unsorted by giving the option `-V', `-1V', or `-2V'. In most cases, the function will be used like this: local expl _description files expl file compadd "$expl[@]" - "$files[@]" Note the use of the parameter expl, the hyphen, and the list of matches. Almost all calls to compadd within the completion system use a similar format; this ensures that user-specified styles are correctly passed down to the builtins which implement the internals of completion. _dir_list [ -s SEP ] [ -S ] Complete a list of directory names separated by colons (the same format as $PATH). -s SEP Use SEP as separator between items. SEP defaults to a colon (`:'). -S Add SEP instead of slash (`/') as an autoremoveable suffix. _dispatch CONTEXT STRING ... This sets the current context to CONTEXT and looks for completion functions to handle this context by hunting through the list of command names or special contexts (as described above for compdef) given as STRINGs. The first completion function to be defined for one of the contexts in the list is used to generate matches. Typically, the last STRING is -default- to cause the function for default completion to be used as a fallback. The function sets the parameter $service to the STRING being tried, and sets the CONTEXT/COMMAND field (the fourth) of the $curcontext parameter to the CONTEXT given as the first argument. _email_addresses [ -c ] [ -n PLUGIN ] Complete email addresses. Addresses are provided by plugins. -c Complete bare localhost@domain.tld addresses, without a name part or a comment. Without this option, RFC822 `FIRSTNAME LASTNAME
' strings are completed. -n PLUGIN Complete aliases from PLUGIN. The following plugins are available by default: _email-ldap (see the filter style), _email-local (completes USER@HOSTNAME Unix addresses), _email-mail (completes aliases from ~/.mailrc), _email-mush, _email-mutt, and _email-pine. Addresses from the _email-FOO plugin are added under the tag `email-FOO'. _Writing plugins_ Plugins are written as separate functions with names starting with `_email-'. They are invoked with the -c option and compadd options. They should either do their own completion or set the $reply array to a list of `ALIAS:ADDRESS' elements and return 300. New plugins will be picked up and run automatically. _files The function _files is a wrapper around _path_files. It supports all of the same functionality, with some enhancements -- notably, it respects the list-dirs-first style, and it allows users to override the behaviour of the -g and -/ options with the file-patterns style. _files should therefore be preferred over _path_files in most cases. This function accepts the full set of options allowed by _path_files, described below. _gnu_generic This function is a simple wrapper around the _arguments function described above. It can be used to determine automatically the long options understood by commands that produce a list when passed the option `--help'. It is intended to be used as a top-level completion function in its own right. For example, to enable option completion for the commands foo and bar, use compdef _gnu_generic foo bar after the call to compinit. The completion system as supplied is conservative in its use of this function, since it is important to be sure the command understands the option `--help'. _guard [ OPTIONS ] PATTERN DESCR This function displays DESCR if PATTERN matches the string to be completed. It is intended to be used in the ACTION for the specifications passed to _arguments and similar functions. The return status is zero if the message was displayed and the word to complete is not empty, and non-zero otherwise. The PATTERN may be preceded by any of the options understood by compadd that are passed down from _description, namely -M, -J, -V, -1, -2, -n, -F and -X. All of these options will be ignored. This fits in conveniently with the argument-passing conventions of actions for _arguments. As an example, consider a command taking the options -n and -none, where -n must be followed by a numeric value in the same word. By using: _arguments '-n-: :_guard "[0-9]#" "numeric value"' '-none' _arguments can be made to both display the message `numeric value' and complete options after `-n'. If the `-n' is already followed by one or more digits (the pattern passed to _guard) only the message will be displayed; if the `-n' is followed by another character, only options are completed. _message [ -r12 ] [ -VJ GROUP ] DESCR _message -e [ TAG ] DESCR The DESCR is used in the same way as the third argument to the _description function, except that the resulting string will always be shown whether or not matches were generated. This is useful for displaying a help message in places where no completions can be generated. The format style is examined with the messages tag to find a message; the usual tag, descriptions, is used only if the style is not set with the former. If the -r option is given, no style is used; the DESCR is taken literally as the string to display. This is most useful when the DESCR comes from a pre-processed argument list which already contains an expanded description. Note that this option does not disable the `%'-sequence parsing done by compadd. The -12VJ options and the GROUP are passed to compadd and hence determine the group the message string is added to. The second -e form gives a description for completions with the tag TAG to be shown even if there are no matches for that tag. This form is called by _arguments in the event that there is no action for an option specification. The tag can be omitted and if so the tag is taken from the parameter $curtag; this is maintained by the completion system and so is usually correct. Note that if there are no matches at the time this function is called, compstate[insert] is cleared, so additional matches generated later are not inserted on the command line. _multi_parts [ -i ] SEP ARRAY The argument SEP is a separator character. The ARRAY may be either the name of an array parameter or a literal array in the form `(foo bar)', a parenthesised list of words separated by whitespace. The possible completions are the strings from the array. However, each chunk delimited by SEP will be completed separately. For example, the _tar function uses `_multi_parts / PATHARRAY' to complete partial file paths from the given array of complete file paths. The -i option causes _multi_parts to insert a unique match even if that requires multiple separators to be inserted. This is not usually the expected behaviour with filenames, but certain other types of completion, for example those with a fixed set of possibilities, may be more suited to this form. Like other utility functions, this function accepts the `-V', `-J', `-1', `-2', `-n', `-f', `-X', `-M', `-P', `-S', `-r', `-R', and `-q' options and passes them to the compadd builtin. _next_label [ -x ] [ -12VJ ] TAG NAME DESCR [ OPTION ... ] This function is used to implement the loop over different tag labels for a particular tag as described above for the tag-order style. On each call it checks to see if there are any more tag labels; if there is it returns status zero, otherwise non-zero. As this function requires a current tag to be set, it must always follow a call to _tags or _requested. The -x12VJ options and the first three arguments are passed to the _description function. Where appropriate the TAG will be replaced by a tag label in this call. Any description given in the tag-order style is preferred to the DESCR passed to _next_label. The OPTIONs given after the DESCR are set in the parameter given by NAME, and hence are to be passed to compadd or whatever function is called to add the matches. Here is a typical use of this function for the tag foo. The call to _requested determines if tag foo is required at all; the loop over _next_label handles any labels defined for the tag in the tag-order style. local expl ret=1 ... if _requested foo; then ... while _next_label foo expl '...'; do compadd "$expl[@]" ... && ret=0 done ... fi return ret _normal [ -P | -p PRECOMMAND ] This is the standard function called to handle completion outside any special -CONTEXT-. It is called both to complete the command word and also the arguments for a command. In the second case, _normal looks for a special completion for that command, and if there is none it uses the completion for the -default- context. A second use is to reexamine the command line specified by the $words array and the $CURRENT parameter after those have been modified. For example, the function _precommand, which completes after precommand specifiers such as nohup, removes the first word from the words array, decrements the CURRENT parameter, then calls `_normal -p $service'. The effect is that `nohup CMD ...' is treated in the same way as `CMD ...'. -P Reset the list of precommands. This option should be used if completing a command line which allows internal commands (e.g. builtins and functions) regardless of prior precommands (e.g. `zsh -c'). -p PRECOMMAND Append PRECOMMAND to the list of precommands. This option should be used in nearly all cases in which -P is not applicable. If the command name matches one of the patterns given by one of the options -p or -P to compdef, the corresponding completion function is called and then the parameter _compskip is checked. If it is set completion is terminated at that point even if no matches have been found. This is the same effect as in the -first- context. _options This can be used to complete the names of shell options. It provides a matcher specification that ignores a leading `no', ignores underscores and allows upper-case letters to match their lower-case counterparts (for example, `glob', `noglob', `NO_GLOB' are all completed). Any arguments are propagated to the compadd builtin. _options_set and _options_unset These functions complete only set or unset options, with the same matching specification used in the _options function. Note that you need to uncomment a few lines in the _main_complete function for these functions to work properly. The lines in question are used to store the option settings in effect before the completion widget locally sets the options it needs. Hence these functions are not generally used by the completion system. _parameters This is used to complete the names of shell parameters. The option `-g PATTERN' limits the completion to parameters whose type matches the PATTERN. The type of a parameter is that shown by `print ${(t)PARAM}', hence judicious use of `*' in PATTERN is probably necessary. All other arguments are passed to the compadd builtin. _path_files This function is used throughout the completion system to complete filenames. It allows completion of partial paths. For example, the string `/u/i/s/sig' may be completed to `/usr/include/sys/signal.h'. The options accepted by both _path_files and _files are: -f Complete all filenames. This is the default. -/ Specifies that only directories should be completed. -g PATTERN Specifies that only files matching the PATTERN should be completed. -W PATHS Specifies path prefixes that are to be prepended to the string from the command line to generate the filenames but that should not be inserted as completions nor shown in completion listings. Here, PATHS may be the name of an array parameter, a literal list of paths enclosed in parentheses or an absolute pathname. -F IGNORED-FILES This behaves as for the corresponding option to the compadd builtin. It gives direct control over which filenames should be ignored. If the option is not present, the ignored-patterns style is used. Both _path_files and _files also accept the following options which are passed to compadd: `-J', `-V', `-1', `-2', `-n', `-X', `-M', `-P', `-S', `-q', `-r', and `-R'. Finally, the _path_files function uses the styles expand, ambiguous, special-dirs, list-suffixes and file-sort described above. _pick_variant [ -b BUILTIN-LABEL ] [ -c COMMAND ] [ -r NAME ] LABEL=PATTERN ... LABEL [ ARG ... ] This function is used to resolve situations where a single command name requires more than one type of handling, either because it has more than one variant or because there is a name clash between two different commands. The command to run is taken from the first element of the array words unless this is overridden by the option -c. This command is run and its output is compared with a series of patterns. Arguments to be passed to the command can be specified at the end after all the other arguments. The patterns to try in order are given by the arguments LABEL=PATTERN; if the output of `COMMAND ARG ...' contains PATTERN, then LABEL is selected as the label for the command variant. If none of the patterns match, the final command label is selected and status 1 is returned. If the `-b BUILTIN-LABEL' is given, the command is tested to see if it is provided as a shell builtin, possibly autoloaded; if so, the label BUILTIN-LABEL is selected as the label for the variant. If the `-r NAME' is given, the LABEL picked is stored in the parameter named NAME. The results are also cached in the _cmd_variant associative array indexed by the name of the command run. _regex_arguments NAME SPEC ... This function generates a completion function NAME which matches the specifications SPECs, a set of regular expressions as described below. After running _regex_arguments, the function NAME should be called as a normal completion function. The pattern to be matched is given by the contents of the words array up to the current cursor position joined together with null characters; no quotation is applied. The arguments are grouped as sets of alternatives separated by `|', which are tried one after the other until one matches. Each alternative consists of a one or more specifications which are tried left to right, with each pattern matched being stripped in turn from the command line being tested, until all of the group succeeds or until one fails; in the latter case, the next alternative is tried. This structure can be repeated to arbitrary depth by using parentheses; matching proceeds from inside to outside. A special procedure is applied if no test succeeds but the remaining command line string contains no null character (implying the remaining word is the one for which completions are to be generated). The completion target is restricted to the remaining word and any ACTIONs for the corresponding patterns are executed. In this case, nothing is stripped from the command line string. The order of evaluation of the ACTIONs can be determined by the tag-order style; the various formats supported by _alternative can be used in ACTION. The DESCR is used for setting up the array parameter expl. Specification arguments take one of following forms, in which metacharacters such as `(', `)', `#' and `|' should be quoted. /PATTERN/ [%LOOKAHEAD%] [-GUARD] [:TAG:DESCR:ACTION] This is a single primitive component. The function tests whether the combined pattern `(#b)((#B)PATTERN)LOOKAHEAD*' matches the command line string. If so, `GUARD' is evaluated and its return status is examined to determine if the test has succeeded. The PATTERN string `[]' is guaranteed never to match. The LOOKAHEAD is not stripped from the command line before the next pattern is examined. The argument starting with : is used in the same manner as an argument to _alternative. A component is used as follows: PATTERN is tested to see if the component already exists on the command line. If it does, any following specifications are examined to find something to complete. If a component is reached but no such pattern exists yet on the command line, the string containing the ACTION is used to generate matches to insert at that point. /PATTERN/+ [%LOOKAHEAD%] [-GUARD] [:TAG:DESCR:ACTION] This is similar to `/PATTERN/ ...' but the left part of the command line string (i.e. the part already matched by previous patterns) is also considered part of the completion target. /PATTERN/- [%LOOKAHEAD%] [-GUARD] [:TAG:DESCR:ACTION] This is similar to `/PATTERN/ ...' but the ACTIONs of the current and previously matched patterns are ignored even if the following `PATTERN' matches the empty string. ( SPEC ) Parentheses may be used to groups SPECs; note each parenthesis is a single argument to _regex_arguments. SPEC # This allows any number of repetitions of SPEC. SPEC SPEC The two SPECs are to be matched one after the other as described above. SPEC | SPEC Either of the two SPECs can be matched. The function _regex_words can be used as a helper function to generate matches for a set of alternative words possibly with their own arguments as a command line argument. Examples: _regex_arguments _tst /$'[^\0]#\0'/ \ /$'[^\0]#\0'/ :'compadd aaa' This generates a function _tst that completes aaa as its only argument. The TAG and DESCRIPTION for the action have been omitted for brevity (this works but is not recommended in normal use). The first component matches the command word, which is arbitrary; the second matches any argument. As the argument is also arbitrary, any following component would not depend on aaa being present. _regex_arguments _tst /$'[^\0]#\0'/ \ /$'aaa\0'/ :'compadd aaa' This is a more typical use; it is similar, but any following patterns would only match if aaa was present as the first argument. _regex_arguments _tst /$'[^\0]#\0'/ \( \ /$'aaa\0'/ :'compadd aaa' \ /$'bbb\0'/ :'compadd bbb' \) \# In this example, an indefinite number of command arguments may be completed. Odd arguments are completed as aaa and even arguments as bbb. Completion fails unless the set of aaa and bbb arguments before the current one is matched correctly. _regex_arguments _tst /$'[^\0]#\0'/ \ \( /$'aaa\0'/ :'compadd aaa' \| \ /$'bbb\0'/ :'compadd bbb' \) \# This is similar, but either aaa or bbb may be completed for any argument. In this case _regex_words could be used to generate a suitable expression for the arguments. _regex_words TAG DESCRIPTION SPEC ... This function can be used to generate arguments for the _regex_arguments command which may be inserted at any point where a set of rules is expected. The TAG and DESCRIPTION give a standard tag and description pertaining to the current context. Each SPEC contains two or three arguments separated by a colon: note that there is no leading colon in this case. Each SPEC gives one of a set of words that may be completed at this point, together with arguments. It is thus roughly equivalent to the _arguments function when used in normal (non-regex) completion. The part of the SPEC before the first colon is the word to be completed. This may contain a *; the entire word, before and after the * is completed, but only the text before the * is required for the context to be matched, so that further arguments may be completed after the abbreviated form. The second part of SPEC is a description for the word being completed. The optional third part of the SPEC describes how words following the one being completed are themselves to be completed. It will be evaluated in order to avoid problems with quoting. This means that typically it contains a reference to an array containing previously generated regex arguments. The option -t TERM specifies a terminator for the word instead of the usual space. This is handled as an auto-removable suffix in the manner of the option -s SEP to _values. The result of the processing by _regex_words is placed in the array reply, which should be made local to the calling function. If the set of words and arguments may be matched repeatedly, a # should be appended to the generated array at that point. For example: local -a reply _regex_words mydb-commands 'mydb commands' \ 'add:add an entry to mydb:$mydb_add_cmds' \ 'show:show entries in mydb' _regex_arguments _mydb "$reply[@]" _mydb "$@" This shows a completion function for a command mydb which takes two command arguments, add and show. show takes no arguments, while the arguments for add have already been prepared in an array mydb_add_cmds, quite possibly by a previous call to _regex_words. _requested [ -x ] [ -12VJ ] TAG [ NAME DESCR [ COMMAND [ ARG ... ] ] This function is called to decide whether a tag already registered by a call to _tags (see below) has been requested by the user and hence completion should be performed for it. It returns status zero if the tag is requested and non-zero otherwise. The function is typically used as part of a loop over different tags as follows: _tags foo bar baz while _tags; do if _requested foo; then ... # perform completion for foo fi ... # test the tags bar and baz in the same way ... # exit loop if matches were generated done Note that the test for whether matches were generated is not performed until the end of the _tags loop. This is so that the user can set the tag-order style to specify a set of tags to be completed at the same time. If NAME and DESCR are given, _requested calls the _description function with these arguments together with the options passed to _requested. If COMMAND is given, the _all_labels function will be called immediately with the same arguments. In simple cases this makes it possible to perform the test for the tag and the matching in one go. For example: local expl ret=1 _tags foo bar baz while _tags; do _requested foo expl 'description' \ compadd foobar foobaz && ret=0 ... (( ret )) || break done If the COMMAND is not compadd, it must nevertheless be prepared to handle the same options. _retrieve_cache CACHE_IDENTIFIER This function retrieves completion information from the file given by CACHE_IDENTIFIER, stored in a directory specified by the cache-path style which defaults to ~/.zcompcache. The return status is zero if retrieval was successful. It will only attempt retrieval if the use-cache style is set, so you can call this function without worrying about whether the user wanted to use the caching layer. See _store_cache below for more details. _sep_parts This function is passed alternating arrays and separators as arguments. The arrays specify completions for parts of strings to be separated by the separators. The arrays may be the names of array parameters or a quoted list of words in parentheses. For example, with the array `hosts=(ftp news)' the call `_sep_parts '(foo bar)' @ hosts' will complete the string `f' to `foo' and the string `b@n' to `bar@news'. This function accepts the compadd options `-V', `-J', `-1', `-2', `-n', `-X', `-M', `-P', `-S', `-r', `-R', and `-q' and passes them on to the compadd builtin used to add the matches. _sequence [ -s SEP ] [ -n MAX ] [ -d ] FUNCTION [ - ] ... This function is a wrapper to other functions for completing items in a separated list. The same function is used to complete each item in the list. The separator is specified with the -s option. If -s is omitted it will use `,'. Duplicate values are not matched unless -d is specified. If there is a fixed or maximum number of items in the list, this can be specified with the -n option. Common compadd options are passed on to the function. It is possible to use compadd directly with _sequence, though _values may be more appropriate in this situation. _setup TAG [ GROUP ] This function sets up the special parameters used by the completion system appropriately for the TAG given as the first argument. It uses the styles list-colors, list-packed, list-rows-first, last-prompt, accept-exact, menu and force-list. The optional GROUP supplies the name of the group in which the matches will be placed. If it is not given, the TAG is used as the group name. This function is called automatically from _description and hence is not normally called explicitly. _store_cache CACHE_IDENTIFIER PARAM ... This function, together with _retrieve_cache and _cache_invalid, implements a caching layer which can be used in any completion function. Data obtained by costly operations are stored in parameters; this function then dumps the values of those parameters to a file. The data can then be retrieved quickly from that file via _retrieve_cache, even in different instances of the shell. The CACHE_IDENTIFIER specifies the file which the data should be dumped to. The file is stored in a directory specified by the cache-path style which defaults to ~/.zcompcache. The remaining PARAMs arguments are the parameters to dump to the file. The return status is zero if storage was successful. The function will only attempt storage if the use-cache style is set, so you can call this function without worrying about whether the user wanted to use the caching layer. The completion function may avoid calling _retrieve_cache when it already has the completion data available as parameters. However, in that case it should call _cache_invalid to check whether the data in the parameters and in the cache are still valid. See the _perl_modules completion function for a simple example of the usage of the caching layer. _tags [ [ -C NAME ] TAG ... ] If called with arguments, these are taken to be the names of tags valid for completions in the current context. These tags are stored internally and sorted by using the tag-order style. Next, _tags is called repeatedly without arguments from the same completion function. This successively selects the first, second, etc. set of tags requested by the user. The return status is zero if at least one of the tags is requested and non-zero otherwise. To test if a particular tag is to be tried, the _requested function should be called (see above). If `-C NAME' is given, NAME is temporarily stored in the ARGUMENT field (the fifth) of the context in the curcontext parameter during the call to _tags; the field is restored on exit. This allows _tags to use a more specific context without having to change and reset the curcontext parameter (which has the same effect). _tilde_files Like _files, but resolve leading tildes according to the rules of filename expansion, so the suggested completions don't start with a `~' even if the filename on the command-line does. _values [ -O NAME ] [ -s SEP ] [ -S SEP ] [ -wC ] DESC SPEC ... This is used to complete arbitrary keywords (values) and their arguments, or lists of such combinations. If the first argument is the option `-O NAME', it will be used in the same way as by the _arguments function. In other words, the elements of the NAME array will be passed to compadd when executing an action. If the first argument (or the first argument after `-O NAME') is `-s', the next argument is used as the character that separates multiple values. This character is automatically added after each value in an auto-removable fashion (see below); all values completed by `_values -s' appear in the same word on the command line, unlike completion using _arguments. If this option is not present, only a single value will be completed per word. Normally, _values will only use the current word to determine which values are already present on the command line and hence are not to be completed again. If the -w option is given, other arguments are examined as well. The first non-option argument, DESC, is used as a string to print as a description before listing the values. All other arguments describe the possible values and their arguments in the same format used for the description of options by the _arguments function (see above). The only differences are that no minus or plus sign is required at the beginning, values can have only one argument, and the forms of action beginning with an equal sign are not supported. The character separating a value from its argument can be set using the option -S (like -s, followed by the character to use as the separator in the next argument). By default the equals sign will be used as the separator between values and arguments. Example: _values -s , 'description' \ '*foo[bar]' \ '(two)*one[number]:first count:' \ 'two[another number]::second count:(1 2 3)' This describes three possible values: `foo', `one', and `two'. The first is described as `bar', takes no argument and may appear more than once. The second is described as `number', may appear more than once, and takes one mandatory argument described as `first count'; no action is specified, so it will not be completed. The `(two)' at the beginning says that if the value `one' is on the line, the value `two' will no longer be considered a possible completion. Finally, the last value (`two') is described as `another number' and takes an optional argument described as `second count' for which the completions (to appear after an `=') are `1', `2', and `3'. The _values function will complete lists of these values separated by commas. Like _arguments, this function temporarily adds another context name component to the arguments element (the fifth) of the current context while executing the ACTION. Here this name is just the name of the value for which the argument is completed. The style verbose is used to decide if the descriptions for the values (but not those for the arguments) should be printed. The associative array val_args is used to report values and their arguments; this works similarly to the opt_args associative array used by _arguments. Hence the function calling _values should declare the local parameters state, state_descr, line, context and val_args: local context state state_descr line typeset -A val_args when using an action of the form `->STRING'. With this function the context parameter will be set to the name of the value whose argument is to be completed. Note that for _values, the state and state_descr are scalars rather than arrays. Only a single matching state is returned. Note also that _values normally adds the character used as the separator between values as an auto-removable suffix (similar to a `/' after a directory). However, this is not possible for a `->STRING' action as the matches for the argument are generated by the calling function. To get the usual behaviour, the calling function can add the separator X as a suffix by passing the options `-qS X' either directly or indirectly to compadd. The option -C is treated in the same way as it is by _arguments. In that case the parameter curcontext should be made local instead of context (as described above). _wanted [ -x ] [ -C NAME ] [ -12VJ ] TAG NAME DESCR COMMAND [ ARG ...] In many contexts, completion can only generate one particular set of matches, usually corresponding to a single tag. However, it is still necessary to decide whether the user requires matches of this type. This function is useful in such a case. The arguments to _wanted are the same as those to _requested, i.e. arguments to be passed to _description. However, in this case the COMMAND is not optional; all the processing of tags, including the loop over both tags and tag labels and the generation of matches, is carried out automatically by _wanted. Hence to offer only one tag and immediately add the corresponding matches with the given description: local expl _wanted tag expl 'description' \ compadd matches... Note that, as for _requested, the COMMAND must be able to accept options to be passed down to compadd. Like _tags this function supports the -C option to give a different name for the argument context field. The -x option has the same meaning as for _description. _widgets [ -g PATTERN ] This function completes names of zle widgets (see *Note Zle Widgets::). The PATTERN, if present, is matched against values of the $widgets special parameter, documented in *Note The zsh/zleparameter Module::.  File: zsh.info, Node: Completion System Variables, Next: Completion Directories, Prev: Completion Functions, Up: Completion System 20.7 Completion System Variables ================================ There are some standard variables, initialised by the _main_complete function and then used from other functions. The standard variables are: _comp_caller_options The completion system uses setopt to set a number of options. This allows functions to be written without concern for compatibility with every possible combination of user options. However, sometimes completion needs to know what the user's option preferences are. These are saved in the _comp_caller_options associative array. Option names, spelled in lowercase without underscores, are mapped to one or other of the strings `on' and `off'. _comp_priv_prefix Completion functions such as _sudo can set the _comp_priv_prefix array to a command prefix that may then be used by _call_program to match the privileges when calling programs to generate matches. Two more features are offered by the _main_complete function. The arrays compprefuncs and comppostfuncs may contain names of functions that are to be called immediately before or after completion has been tried. A function will only be called once unless it explicitly reinserts itself into the array.  File: zsh.info, Node: Completion Directories, Prev: Completion System Variables, Up: Completion System 20.8 Completion Directories =========================== In the source distribution, the files are contained in various subdirectories of the Completion directory. They may have been installed in the same structure, or into one single function directory. The following is a description of the files found in the original directory structure. If you wish to alter an installed file, you will need to copy it to some directory which appears earlier in your fpath than the standard directory where it appears. Base The core functions and special completion widgets automatically bound to keys. You will certainly need most of these, though will probably not need to alter them. Many of these are documented above. Zsh Functions for completing arguments of shell builtin commands and utility functions for this. Some of these are also used by functions from the Unix directory. Unix Functions for completing arguments of external commands and suites of commands. They may need modifying for your system, although in many cases some attempt is made to decide which version of a command is present. For example, completion for the mount command tries to determine the system it is running on, while completion for many other utilities try to decide whether the GNU version of the command is in use, and hence whether the --help option is supported. X, AIX, BSD, ... Completion and utility function for commands available only on some systems. These are not arranged hierarchically, so, for example, both the Linux and Debian directories, as well as the X directory, may be useful on your system.  File: zsh.info, Node: Completion Using compctl, Next: Zsh Modules, Prev: Completion System, Up: Top 21 Completion Using compctl *************************** 21.1 Types of completion ======================== This version of zsh has two ways of performing completion of words on the command line. New users of the shell may prefer to use the newer and more powerful system based on shell functions; this is described in *Note Completion System::, and the basic shell mechanisms which support it are described in *Note Completion Widgets::. This chapter describes the older compctl command. 21.2 Description ================ compctl [ -CDT ] OPTIONS [ COMMAND ... ] compctl [ -CDT ] OPTIONS [ -x PATTERN OPTIONS - ... -- ] [ + OPTIONS [ -x ... -- ] ... [+] ] [ COMMAND ... ] compctl -M MATCH-SPECS ... compctl -L [ -CDTM ] [ COMMAND ... ] compctl + COMMAND ... Control the editor's completion behavior according to the supplied set of OPTIONS. Various editing commands, notably expand-or-complete-word, usually bound to tab, will attempt to complete a word typed by the user, while others, notably delete-char-or-list, usually bound to ^D in EMACS editing mode, list the possibilities; compctl controls what those possibilities are. They may for example be filenames (the most common case, and hence the default), shell variables, or words from a user-specified list. * Menu: * Command Flags:: * Option Flags:: * Alternative Completion:: * Extended Completion:: * Example::  File: zsh.info, Node: Command Flags, Next: Option Flags, Up: Completion Using compctl 21.3 Command Flags ================== Completion of the arguments of a command may be different for each command or may use the default. The behavior when completing the command word itself may also be separately specified. These correspond to the following flags and arguments, all of which (except for -L) may be combined with any combination of the OPTIONS described subsequently in *Note Option Flags::: COMMAND ... controls completion for the named commands, which must be listed last on the command line. If completion is attempted for a command with a pathname containing slashes and no completion definition is found, the search is retried with the last pathname component. If the command starts with a =, completion is tried with the pathname of the command. Any of the COMMAND strings may be patterns of the form normally used for filename generation. These should be quoted to protect them from immediate expansion; for example the command string 'foo*' arranges for completion of the words of any command beginning with foo. When completion is attempted, all pattern completions are tried in the reverse order of their definition until one matches. By default, completion then proceeds as normal, i.e. the shell will try to generate more matches for the specific command on the command line; this can be overridden by including -tn in the flags for the pattern completion. Note that aliases are expanded before the command name is determined unless the COMPLETE_ALIASES option is set. Commands may not be combined with the -C, -D or -T flags. -C controls completion when the command word itself is being completed. If no compctl -C command has been issued, the names of any executable command (whether in the path or specific to the shell, such as aliases or functions) are completed. -D controls default completion behavior for the arguments of commands not assigned any special behavior. If no compctl -D command has been issued, filenames are completed. -T supplies completion flags to be used before any other processing is done, even before processing for compctls defined for specific commands. This is especially useful when combined with extended completion (the -x flag, see *Note Extended Completion:: below). Using this flag you can define default behavior which will apply to all commands without exception, or you can alter the standard behavior for all commands. For example, if your access to the user database is too slow and/or it contains too many users (so that completion after `~' is too slow to be usable), you can use compctl -T -x 's[~] C[0,[^/]#]' -k friends -S/ -tn to complete the strings in the array friends after a `~'. The C[...] argument is necessary so that this form of ~-completion is not tried after the directory name is finished. -L lists the existing completion behavior in a manner suitable for putting into a start-up script; the existing behavior is not changed. Any combination of the above forms, or the -M flag (which must follow the -L flag), may be specified, otherwise all defined completions are listed. Any other flags supplied are ignored. _no argument_ If no argument is given, compctl lists all defined completions in an abbreviated form; with a list of OPTIONS, all completions with those flags set (not counting extended completion) are listed. If the + flag is alone and followed immediately by the COMMAND list, the completion behavior for all the commands in the list is reset to the default. In other words, completion will subsequently use the options specified by the -D flag. The form with -M as the first and only option defines global matching specifications (see *Note Completion Matching Control::). The match specifications given will be used for every completion attempt (only when using compctl, not with the new completion system) and are tried in the order in which they are defined until one generates at least one match. E.g.: compctl -M '' 'm:{a-zA-Z}={A-Za-z}' This will first try completion without any global match specifications (the empty string) and, if that generates no matches, will try case insensitive completion.  File: zsh.info, Node: Option Flags, Next: Alternative Completion, Prev: Command Flags, Up: Completion Using compctl 21.4 Option Flags ================= [ -fcFBdeaRGovNAIOPZEnbjrzu/12 ] [ -k ARRAY ] [ -g GLOBSTRING ] [ -s SUBSTSTRING ] [ -K FUNCTION ] [ -Q ] [ -P PREFIX ] [ -S SUFFIX ] [ -W FILE-PREFIX ] [ -H NUM PATTERN ] [ -q ] [ -X EXPLANATION ] [ -Y EXPLANATION ] [ -y FUNC-OR-VAR ] [ -l CMD ] [ -h CMD ] [ -U ] [ -t CONTINUE ] [ -J NAME ] [ -V NAME ] [ -M MATCH-SPEC ] The remaining OPTIONS specify the type of command arguments to look for during completion. Any combination of these flags may be specified; the result is a sorted list of all the possibilities. The options are as follows. * Menu: * Simple Flags:: * Flags with Arguments:: * Control Flags::  File: zsh.info, Node: Simple Flags, Next: Flags with Arguments, Up: Option Flags 21.4.1 Simple Flags ------------------- These produce completion lists made up by the shell itself: -f Filenames and file system paths. -/ Just file system paths. -c Command names, including aliases, shell functions, builtins and reserved words. -F Function names. -B Names of builtin commands. -m Names of external commands. -w Reserved words. -a Alias names. -R Names of regular (non-global) aliases. -G Names of global aliases. -d This can be combined with -F, -B, -w, -a, -R and -G to get names of disabled functions, builtins, reserved words or aliases. -e This option (to show enabled commands) is in effect by default, but may be combined with -d; -de in combination with -F, -B, -w, -a, -R and -G will complete names of functions, builtins, reserved words or aliases whether or not they are disabled. -o Names of shell options (see *Note Options::). -v Names of any variable defined in the shell. -N Names of scalar (non-array) parameters. -A Array names. -I Names of integer variables. -O Names of read-only variables. -p Names of parameters used by the shell (including special parameters). -Z Names of shell special parameters. -E Names of environment variables. -n Named directories. -b Key binding names. -j Job names: the first word of the job leader's command line. This is useful with the kill builtin. -r Names of running jobs. -z Names of suspended jobs. -u User names.  File: zsh.info, Node: Flags with Arguments, Next: Control Flags, Prev: Simple Flags, Up: Option Flags 21.4.2 Flags with Arguments --------------------------- These have user supplied arguments to determine how the list of completions is to be made up: -k ARRAY Names taken from the elements of $ARRAY (note that the `$' does not appear on the command line). Alternatively, the argument ARRAY itself may be a set of space- or comma-separated values in parentheses, in which any delimiter may be escaped with a backslash; in this case the argument should be quoted. For example, compctl -k "(cputime filesize datasize stacksize coredumpsize resident descriptors)" limit -g GLOBSTRING The GLOBSTRING is expanded using filename globbing; it should be quoted to protect it from immediate expansion. The resulting filenames are taken as the possible completions. Use `*(/)' instead of `*/' for directories. The fignore special parameter is not applied to the resulting files. More than one pattern may be given separated by blanks. (Note that brace expansion is _not_ part of globbing. Use the syntax `(either|or)' to match alternatives.) -s SUBSTSTRING The SUBSTSTRING is split into words and these words are than expanded using all shell expansion mechanisms (see *Note Expansion::). The resulting words are taken as possible completions. The fignore special parameter is not applied to the resulting files. Note that -g is faster for filenames. -K FUNCTION Call the given function to get the completions. Unless the name starts with an underscore, the function is passed two arguments: the prefix and the suffix of the word on which completion is to be attempted, in other words those characters before the cursor position, and those from the cursor position onwards. The whole command line can be accessed with the -c and -l flags of the read builtin. The function should set the variable reply to an array containing the completions (one completion per element); note that reply should not be made local to the function. From such a function the command line can be accessed with the -c and -l flags to the read builtin. For example, function whoson { reply=(`users`); } compctl -K whoson talk completes only logged-on users after `talk'. Note that `whoson' must return an array, so `reply=`users`' would be incorrect. -H NUM PATTERN The possible completions are taken from the last NUM history lines. Only words matching PATTERN are taken. If NUM is zero or negative the whole history is searched and if PATTERN is the empty string all words are taken (as with `*'). A typical use is compctl -D -f + -H 0 '' which forces completion to look back in the history list for a word if no filename matches.  File: zsh.info, Node: Control Flags, Prev: Flags with Arguments, Up: Option Flags 21.4.3 Control Flags -------------------- These do not directly specify types of name to be completed, but manipulate the options that do: -Q This instructs the shell not to quote any metacharacters in the possible completions. Normally the results of a completion are inserted into the command line with any metacharacters quoted so that they are interpreted as normal characters. This is appropriate for filenames and ordinary strings. However, for special effects, such as inserting a backquoted expression from a completion array (-k) so that the expression will not be evaluated until the complete line is executed, this option must be used. -P PREFIX The PREFIX is inserted just before the completed string; any initial part already typed will be completed and the whole PREFIX ignored for completion purposes. For example, compctl -j -P "%" kill inserts a `%' after the kill command and then completes job names. -S SUFFIX When a completion is found the SUFFIX is inserted after the completed string. In the case of menu completion the suffix is inserted immediately, but it is still possible to cycle through the list of completions by repeatedly hitting the same key. -W FILE-PREFIX With directory FILE-PREFIX: for command, file, directory and globbing completion (options -c, -f, -/, -g), the file prefix is implicitly added in front of the completion. For example, compctl -/ -W ~/Mail maildirs completes any subdirectories to any depth beneath the directory ~/Mail, although that prefix does not appear on the command line. The FILE-PREFIX may also be of the form accepted by the -k flag, i.e. the name of an array or a literal list in parenthesis. In this case all the directories in the list will be searched for possible completions. -q If used with a suffix as specified by the -S option, this causes the suffix to be removed if the next character typed is a blank or does not insert anything or if the suffix consists of only one character and the next character typed is the same character; this the same rule used for the AUTO_REMOVE_SLASH option. The option is most useful for list separators (comma, colon, etc.). -l CMD This option restricts the range of command line words that are considered to be arguments. If combined with one of the extended completion patterns `p[...]', `r[...]', or `R[...]' (see *Note Extended Completion:: below) the range is restricted to the range of arguments specified in the brackets. Completion is then performed as if these had been given as arguments to the CMD supplied with the option. If the CMD string is empty the first word in the range is instead taken as the command name, and command name completion performed on the first word in the range. For example, compctl -x 'r[-exec,;]' -l '' -- find completes arguments between `-exec' and the following `;' (or the end of the command line if there is no such string) as if they were a separate command line. -h CMD Normally zsh completes quoted strings as a whole. With this option, completion can be done separately on different parts of such strings. It works like the -l option but makes the completion code work on the parts of the current word that are separated by spaces. These parts are completed as if they were arguments to the given CMD. If CMD is the empty string, the first part is completed as a command name, as with -l. -U Use the whole list of possible completions, whether or not they actually match the word on the command line. The word typed so far will be deleted. This is most useful with a function (given by the -K option) which can examine the word components passed to it (or via the read builtin's -c and -l flags) and use its own criteria to decide what matches. If there is no completion, the original word is retained. Since the produced possible completions seldom have interesting common prefixes and suffixes, menu completion is started immediately if AUTO_MENU is set and this flag is used. -y FUNC-OR-VAR The list provided by FUNC-OR-VAR is displayed instead of the list of completions whenever a listing is required; the actual completions to be inserted are not affected. It can be provided in two ways. Firstly, if FUNC-OR-VAR begins with a $ it defines a variable, or if it begins with a left parenthesis a literal array, which contains the list. A variable may have been set by a call to a function using the -K option. Otherwise it contains the name of a function which will be executed to create the list. The function will be passed as an argument list all matching completions, including prefixes and suffixes expanded in full, and should set the array reply to the result. In both cases, the display list will only be retrieved after a complete list of matches has been created. Note that the returned list does not have to correspond, even in length, to the original set of matches, and may be passed as a scalar instead of an array. No special formatting of characters is performed on the output in this case; in particular, newlines are printed literally and if they appear output in columns is suppressed. -X EXPLANATION Print EXPLANATION when trying completion on the current set of options. A `%n' in this string is replaced by the number of matches that were added for this explanation string. The explanation only appears if completion was tried and there was no unique match, or when listing completions. Explanation strings will be listed together with the matches of the group specified together with the -X option (using the -J or -V option). If the same explanation string is given to multiple -X options, the string appears only once (for each group) and the number of matches shown for the `%n' is the total number of all matches for each of these uses. In any case, the explanation string will only be shown if there was at least one match added for the explanation string. The sequences %B, %b, %S, %s, %U, and %u specify output attributes (bold, standout, and underline), %F, %f, %K, %k specify foreground and background colours, and %{...%} can be used to include literal escape sequences as in prompts. -Y EXPLANATION Identical to -X, except that the EXPLANATION first undergoes expansion following the usual rules for strings in double quotes. The expansion will be carried out after any functions are called for the -K or -y options, allowing them to set variables. -t CONTINUE The CONTINUE-string contains a character that specifies which set of completion flags should be used next. It is useful: (i) With -T, or when trying a list of pattern completions, when compctl would usually continue with ordinary processing after finding matches; this can be suppressed with `-tn'. (ii) With a list of alternatives separated by +, when compctl would normally stop when one of the alternatives generates matches. It can be forced to consider the next set of completions by adding `-t+' to the flags of the alternative before the `+'. (iii) In an extended completion list (see below), when compctl would normally continue until a set of conditions succeeded, then use only the immediately following flags. With `-t-', compctl will continue trying extended completions after the next `-'; with `-tx' it will attempt completion with the default flags, in other words those before the `-x'. -J NAME This gives the name of the group the matches should be placed in. Groups are listed and sorted separately; likewise, menu completion will offer the matches in the groups in the order in which the groups were defined. If no group name is explicitly given, the matches are stored in a group named default. The first time a group name is encountered, a group with that name is created. After that all matches with the same group name are stored in that group. This can be useful with non-exclusive alternative completions. For example, in compctl -f -J files -t+ + -v -J variables foo both files and variables are possible completions, as the -t+ forces both sets of alternatives before and after the + to be considered at once. Because of the -J options, however, all files are listed before all variables. -V NAME Like -J, but matches within the group will not be sorted in listings nor in menu completion. These unsorted groups are in a different name space from the sorted ones, so groups defined as -J files and -V files are distinct. -1 If given together with the -V option, makes only consecutive duplicates in the group be removed. Note that groups with and without this flag are in different name spaces. -2 If given together with the -J or -V option, makes all duplicates be kept. Again, groups with and without this flag are in different name spaces. -M MATCH-SPEC This defines additional matching control specifications that should be used only when testing words for the list of flags this flag appears in. The format of the MATCH-SPEC string is described in *Note Completion Matching Control::.  File: zsh.info, Node: Alternative Completion, Next: Extended Completion, Prev: Option Flags, Up: Completion Using compctl 21.5 Alternative Completion =========================== compctl [ -CDT ] OPTIONS + OPTIONS [ + ... ] [ + ] COMMAND ... The form with `+' specifies alternative options. Completion is tried with the options before the first `+'. If this produces no matches completion is tried with the flags after the `+' and so on. If there are no flags after the last `+' and a match has not been found up to that point, default completion is tried. If the list of flags contains a -t with a + character, the next list of flags is used even if the current list produced matches.  File: zsh.info, Node: Extended Completion, Next: Example, Prev: Alternative Completion, Up: Completion Using compctl Additional options are available that restrict completion to some part of the command line; this is referred to as `extended completion'. 21.6 Extended Completion ======================== compctl [ -CDT ] OPTIONS -x PATTERN OPTIONS - ... -- [ COMMAND ... ] compctl [ -CDT ] OPTIONS [ -x PATTERN OPTIONS - ... -- ] [ + OPTIONS [ -x ... -- ] ... [+] ] [ COMMAND ... ] The form with `-x' specifies extended completion for the commands given; as shown, it may be combined with alternative completion using `+'. Each PATTERN is examined in turn; when a match is found, the corresponding OPTIONS, as described in *Note Option Flags:: above, are used to generate possible completions. If no PATTERN matches, the OPTIONS given before the -x are used. Note that each pattern should be supplied as a single argument and should be quoted to prevent expansion of metacharacters by the shell. A PATTERN is built of sub-patterns separated by commas; it matches if at least one of these sub-patterns matches (they are `or'ed). These sub-patterns are in turn composed of other sub-patterns separated by white spaces which match if all of the sub-patterns match (they are `and'ed). An element of the sub-patterns is of the form `C[...][...]', where the pairs of brackets may be repeated as often as necessary, and matches if any of the sets of brackets match (an `or'). The example below makes this clearer. The elements may be any of the following: s[STRING]... Matches if the current word on the command line starts with one of the strings given in brackets. The STRING is not removed and is not part of the completion. S[STRING]... Like s[STRING] except that the STRING is part of the completion. p[FROM,TO]... Matches if the number of the current word is between one of the FROM and TO pairs inclusive. The comma and TO are optional; TO defaults to the same value as FROM. The numbers may be negative: -N refers to the N'th last word on the line. c[OFFSET,STRING]... Matches if the STRING matches the word offset by OFFSET from the current word position. Usually OFFSET will be negative. C[OFFSET,PATTERN]... Like c but using pattern matching instead. w[INDEX,STRING]... Matches if the word in position INDEX is equal to the corresponding STRING. Note that the word count is made after any alias expansion. W[INDEX,PATTERN]... Like w but using pattern matching instead. n[INDEX,STRING]... Matches if the current word contains STRING. Anything up to and including the INDEXth occurrence of this string will not be considered part of the completion, but the rest will. INDEX may be negative to count from the end: in most cases, INDEX will be 1 or -1. For example, compctl -s '`users`' -x 'n[1,@]' -k hosts -- talk will usually complete usernames, but if you insert an @ after the name, names from the array HOSTS (assumed to contain hostnames, though you must make the array yourself) will be completed. Other commands such as rcp can be handled similarly. N[INDEX,STRING]... Like n except that the string will be taken as a character class. Anything up to and including the INDEXth occurrence of any of the characters in STRING will not be considered part of the completion. m[MIN,MAX]... Matches if the total number of words lies between MIN and MAX inclusive. r[STR1,STR2]... Matches if the cursor is after a word with prefix STR1. If there is also a word with prefix STR2 on the command line after the one matched by STR1 it matches only if the cursor is before this word. If the comma and STR2 are omitted, it matches if the cursor is after a word with prefix STR1. R[STR1,STR2]... Like r but using pattern matching instead. q[STR]... Matches the word currently being completed is in single quotes and the STR begins with the letter `s', or if completion is done in double quotes and STR starts with the letter `d', or if completion is done in backticks and STR starts with a `b'.  File: zsh.info, Node: Example, Prev: Extended Completion, Up: Completion Using compctl 21.7 Example ============ compctl -u -x 's[+] c[-1,-f],s[-f+]' \ -g '~/Mail/*(:t)' - 's[-f],c[-1,-f]' -f -- mail This is to be interpreted as follows: If the current command is mail, then if ((the current word begins with + and the previous word is -f) or (the current word begins with -f+)), then complete the non-directory part (the `:t' glob modifier) of files in the directory ~/Mail; else if the current word begins with -f or the previous word was -f, then complete any file; else complete user names.  File: zsh.info, Node: Zsh Modules, Next: Calendar Function System, Prev: Completion Using compctl, Up: Top 22 Zsh Modules ************** 22.1 Description ================ Some optional parts of zsh are in modules, separate from the core of the shell. Each of these modules may be linked in to the shell at build time, or can be dynamically linked while the shell is running if the installation supports this feature. Modules are linked at runtime with the zmodload command, see *Note Shell Builtin Commands::. The modules that are bundled with the zsh distribution are: zsh/attr Builtins for manipulating extended attributes (xattr). zsh/cap Builtins for manipulating POSIX.1e (POSIX.6) capability (privilege) sets. zsh/clone A builtin that can clone a running shell onto another terminal. zsh/compctl The compctl builtin for controlling completion. zsh/complete The basic completion code. zsh/complist Completion listing extensions. zsh/computil A module with utility builtins needed for the shell function based completion system. zsh/curses curses windowing commands zsh/datetime Some date/time commands and parameters. zsh/db/gdbm Builtins for managing associative array parameters tied to GDBM databases. zsh/deltochar A ZLE function duplicating EMACS' zap-to-char. zsh/example An example of how to write a module. zsh/files Some basic file manipulation commands as builtins. zsh/langinfo Interface to locale information. zsh/mapfile Access to external files via a special associative array. zsh/mathfunc Standard scientific functions for use in mathematical evaluations. zsh/nearcolor Map colours to the nearest colour in the available palette. zsh/newuser Arrange for files for new users to be installed. zsh/parameter Access to internal hash tables via special associative arrays. zsh/pcre Interface to the PCRE library. zsh/param/private Builtins for managing private-scoped parameters in function context. zsh/regex Interface to the POSIX regex library. zsh/sched A builtin that provides a timed execution facility within the shell. zsh/net/socket Manipulation of Unix domain sockets zsh/stat A builtin command interface to the stat system call. zsh/system A builtin interface to various low-level system features. zsh/net/tcp Manipulation of TCP sockets zsh/termcap Interface to the termcap database. zsh/terminfo Interface to the terminfo database. zsh/zftp A builtin FTP client. zsh/zle The Zsh Line Editor, including the bindkey and vared builtins. zsh/zleparameter Access to internals of the Zsh Line Editor via parameters. zsh/zprof A module allowing profiling for shell functions. zsh/zpty A builtin for starting a command in a pseudo-terminal. zsh/zselect Block and return when file descriptors are ready. zsh/zutil Some utility builtins, e.g. the one for supporting configuration via styles. * Menu: * The zsh/attr Module:: * The zsh/cap Module:: * The zsh/clone Module:: * The zsh/compctl Module:: * The zsh/complete Module:: * The zsh/complist Module:: * The zsh/computil Module:: * The zsh/curses Module:: * The zsh/datetime Module:: * The zsh/db/gdbm Module:: * The zsh/deltochar Module:: * The zsh/example Module:: * The zsh/files Module:: * The zsh/langinfo Module:: * The zsh/mapfile Module:: * The zsh/mathfunc Module:: * The zsh/nearcolor Module:: * The zsh/newuser Module:: * The zsh/parameter Module:: * The zsh/pcre Module:: * The zsh/param/private Module:: * The zsh/regex Module:: * The zsh/sched Module:: * The zsh/net/socket Module:: * The zsh/stat Module:: * The zsh/system Module:: * The zsh/net/tcp Module:: * The zsh/termcap Module:: * The zsh/terminfo Module:: * The zsh/zftp Module:: * The zsh/zle Module:: * The zsh/zleparameter Module:: * The zsh/zprof Module:: * The zsh/zpty Module:: * The zsh/zselect Module:: * The zsh/zutil Module::  File: zsh.info, Node: The zsh/attr Module, Next: The zsh/cap Module, Up: Zsh Modules 22.2 The zsh/attr Module ======================== The zsh/attr module is used for manipulating extended attributes. The -h option causes all commands to operate on symbolic links instead of their targets. The builtins in this module are: zgetattr [ -h ] FILENAME ATTRIBUTE [ PARAMETER ] Get the extended attribute ATTRIBUTE from the specified FILENAME. If the optional argument PARAMETER is given, the attribute is set on that parameter instead of being printed to stdout. zsetattr [ -h ] FILENAME ATTRIBUTE VALUE Set the extended attribute ATTRIBUTE on the specified FILENAME to VALUE. zdelattr [ -h ] FILENAME ATTRIBUTE Remove the extended attribute ATTRIBUTE from the specified FILENAME. zlistattr [ -h ] FILENAME [ PARAMETER ] List the extended attributes currently set on the specified FILENAME. If the optional argument PARAMETER is given, the list of attributes is set on that parameter instead of being printed to stdout. zgetattr and zlistattr allocate memory dynamically. If the attribute or list of attributes grows between the allocation and the call to get them, they return 2. On all other errors, 1 is returned. This allows the calling function to check for this case and retry.  File: zsh.info, Node: The zsh/cap Module, Next: The zsh/clone Module, Prev: The zsh/attr Module, Up: Zsh Modules 22.3 The zsh/cap Module ======================= The zsh/cap module is used for manipulating POSIX.1e (POSIX.6) capability sets. If the operating system does not support this interface, the builtins defined by this module will do nothing. The builtins in this module are: cap [ CAPABILITIES ] Change the shell's process capability sets to the specified CAPABILITIES, otherwise display the shell's current capabilities. getcap FILENAME ... This is a built-in implementation of the POSIX standard utility. It displays the capability sets on each specified FILENAME. setcap CAPABILITIES FILENAME ... This is a built-in implementation of the POSIX standard utility. It sets the capability sets on each specified FILENAME to the specified CAPABILITIES.  File: zsh.info, Node: The zsh/clone Module, Next: The zsh/compctl Module, Prev: The zsh/cap Module, Up: Zsh Modules 22.4 The zsh/clone Module ========================= The zsh/clone module makes available one builtin command: clone TTY Creates a forked instance of the current shell, attached to the specified TTY. In the new shell, the PID, PPID and TTY special parameters are changed appropriately. $! is set to zero in the new shell, and to the new shell's PID in the original shell. The return status of the builtin is zero in both shells if successful, and non-zero on error. The target of clone should be an unused terminal, such as an unused virtual console or a virtual terminal created by xterm -e sh -c 'trap : INT QUIT TSTP; tty; while :; do sleep 100000000; done' Some words of explanation are warranted about this long xterm command line: when doing clone on a pseudo-terminal, some other session ("session" meant as a unix session group, or SID) is already owning the terminal. Hence the cloned zsh cannot acquire the pseudo-terminal as a controlling tty. That means two things: * the job control signals will go to the sh-started-by-xterm process group (that's why we disable INT QUIT and TSTP with trap; otherwise the while loop could get suspended or killed) * the cloned shell will have job control disabled, and the job control keys (control-C, control-\ and control-Z) will not work. This does not apply when cloning to an _unused_ vc. Cloning to a used (and unprepared) terminal will result in two processes reading simultaneously from the same terminal, with input bytes going randomly to either process. clone is mostly useful as a shell built-in replacement for openvt.  File: zsh.info, Node: The zsh/compctl Module, Next: The zsh/complete Module, Prev: The zsh/clone Module, Up: Zsh Modules 22.5 The zsh/compctl Module =========================== The zsh/compctl module makes available two builtin commands. compctl, is the old, deprecated way to control completions for ZLE. See *Note Completion Using compctl::. The other builtin command, compcall can be used in user-defined completion widgets, see *Note Completion Widgets::.  File: zsh.info, Node: The zsh/complete Module, Next: The zsh/complist Module, Prev: The zsh/compctl Module, Up: Zsh Modules 22.6 The zsh/complete Module ============================ The zsh/complete module makes available several builtin commands which can be used in user-defined completion widgets, see *Note Completion Widgets::.  File: zsh.info, Node: The zsh/complist Module, Next: The zsh/computil Module, Prev: The zsh/complete Module, Up: Zsh Modules 22.7 The zsh/complist Module ============================ The zsh/complist module offers three extensions to completion listings: the ability to highlight matches in such a list, the ability to scroll through long lists and a different style of menu completion. 22.7.1 Colored completion listings ---------------------------------- Whenever one of the parameters ZLS_COLORS or ZLS_COLOURS is set and the zsh/complist module is loaded or linked into the shell, completion lists will be colored. Note, however, that complist will not automatically be loaded if it is not linked in: on systems with dynamic loading, `zmodload zsh/complist' is required. The parameters ZLS_COLORS and ZLS_COLOURS describe how matches are highlighted. To turn on highlighting an empty value suffices, in which case all the default values given below will be used. The format of the value of these parameters is the same as used by the GNU version of the ls command: a colon-separated list of specifications of the form `NAME=VALUE'. The NAME may be one of the following strings, most of which specify file types for which the VALUE will be used. The strings and their default values are: no 0 for normal text (i.e. when displaying something other than a matched file) fi 0 for regular files di 32 for directories ln 36 for symbolic links. If this has the special value target, symbolic links are dereferenced and the target file used to determine the display format. pi 31 for named pipes (FIFOs) so 33 for sockets bd 44;37 for block devices cd 44;37 for character devices or NONE for a symlink to nonexistent file (default is the value defined for ln) mi NONE for a non-existent file (default is the value defined for fi); this code is currently not used su 37;41 for files with setuid bit set sg 30;43 for files with setgid bit set tw 30;42 for world writable directories with sticky bit set ow 34;43 for world writable directories without sticky bit set sa NONE for files with an associated suffix alias; this is only tested after specific suffixes, as described below st 37;44 for directories with sticky bit set but not world writable ex 35 for executable files lc \e[ for the left code (see below) rc m for the right code tc 0 for the character indicating the file type printed after filenames if the LIST_TYPES option is set sp 0 for the spaces printed after matches to align the next column ec NONE for the end code Apart from these strings, the NAME may also be an asterisk (`*') followed by any string. The VALUE given for such a string will be used for all files whose name ends with the string. The NAME may also be an equals sign (`=') followed by a pattern; the EXTENDED_GLOB option will be turned on for evaluation of the pattern. The VALUE given for this pattern will be used for all matches (not just filenames) whose display string are matched by the pattern. Definitions for the form with the leading equal sign take precedence over the values defined for file types, which in turn take precedence over the form with the leading asterisk (file extensions). The leading-equals form also allows different parts of the displayed strings to be colored differently. For this, the pattern has to use the `(#b)' globbing flag and pairs of parentheses surrounding the parts of the strings that are to be colored differently. In this case the VALUE may consist of more than one color code separated by equal signs. The first code will be used for all parts for which no explicit code is specified and the following codes will be used for the parts matched by the sub-patterns in parentheses. For example, the specification `=(#b)(?)*(?)=0=3=7' will be used for all matches which are at least two characters long and will use the code `3' for the first character, `7' for the last character and `0' for the rest. All three forms of NAME may be preceded by a pattern in parentheses. If this is given, the VALUE will be used only for matches in groups whose names are matched by the pattern given in the parentheses. For example, `(g*)m*=43' highlights all matches beginning with `m' in groups whose names begin with `g' using the color code `43'. In case of the `lc', `rc', and `ec' codes, the group pattern is ignored. Note also that all patterns are tried in the order in which they appear in the parameter value until the first one matches which is then used. Patterns may be matched against completions, descriptions (possibly with spaces appended for padding), or lines consisting of a completion followed by a description. For consistent coloring it may be necessary to use more than one pattern or a pattern with backreferences. When printing a match, the code prints the value of lc, the value for the file-type or the last matching specification with a `*', the value of rc, the string to display for the match itself, and then the value of ec if that is defined or the values of lc, no, and rc if ec is not defined. The default values are ISO 6429 (ANSI) compliant and can be used on vt100 compatible terminals such as xterms. On monochrome terminals the default values will have no visible effect. The colors function from the contribution can be used to get associative arrays containing the codes for ANSI terminals (see *Note Other Functions::). For example, after loading colors, one could use `$color[red]' to get the code for foreground color red and `$color[bg-green]' for the code for background color green. If the completion system invoked by compinit is used, these parameters should not be set directly because the system controls them itself. Instead, the list-colors style should be used (see *Note Completion System Configuration::). 22.7.2 Scrolling in completion listings --------------------------------------- To enable scrolling through a completion list, the LISTPROMPT parameter must be set. Its value will be used as the prompt; if it is the empty string, a default prompt will be used. The value may contain escapes of the form `%x'. It supports the escapes `%B', `%b', `%S', `%s', `%U', `%u', `%F', `%f', `%K', `%k' and `%{...%}' used also in shell prompts as well as three pairs of additional sequences: a `%l' or `%L' is replaced by the number of the last line shown and the total number of lines in the form `NUMBER/TOTAL'; a `%m' or `%M' is replaced with the number of the last match shown and the total number of matches; and `%p' or `%P' is replaced with `Top', `Bottom' or the position of the first line shown in percent of the total number of lines, respectively. In each of these cases the form with the uppercase letter will be replaced with a string of fixed width, padded to the right with spaces, while the lowercase form will not be padded. If the parameter LISTPROMPT is set, the completion code will not ask if the list should be shown. Instead it immediately starts displaying the list, stopping after the first screenful, showing the prompt at the bottom, waiting for a keypress after temporarily switching to the listscroll keymap. Some of the zle functions have a special meaning while scrolling lists: send-break stops listing discarding the key pressed accept-line, down-history, down-line-or-history down-line-or-search, vi-down-line-or-history scrolls forward one line complete-word, menu-complete, expand-or-complete expand-or-complete-prefix, menu-complete-or-expand scrolls forward one screenful accept-search stop listing but take no other action Every other character stops listing and immediately processes the key as usual. Any key that is not bound in the listscroll keymap or that is bound to undefined-key is looked up in the keymap currently selected. As for the ZLS_COLORS and ZLS_COLOURS parameters, LISTPROMPT should not be set directly when using the shell function based completion system. Instead, the list-prompt style should be used. 22.7.3 Menu selection --------------------- The zsh/complist module also offers an alternative style of selecting matches from a list, called menu selection, which can be used if the shell is set up to return to the last prompt after showing a completion list (see the ALWAYS_LAST_PROMPT option in *Note Options::). Menu selection can be invoked directly by the widget menu-select defined by this module. This is a standard ZLE widget that can be bound to a key in the usual way as described in *Note Zsh Line Editor::. Alternatively, the parameter MENUSELECT can be set to an integer, which gives the minimum number of matches that must be present before menu selection is automatically turned on. This second method requires that menu completion be started, either directly from a widget such as menu-complete, or due to one of the options MENU_COMPLETE or AUTO_MENU being set. If MENUSELECT is set, but is 0, 1 or empty, menu selection will always be started during an ambiguous menu completion. When using the completion system based on shell functions, the MENUSELECT parameter should not be used (like the ZLS_COLORS and ZLS_COLOURS parameters described above). Instead, the menu style should be used with the select=... keyword. After menu selection is started, the matches will be listed. If there are more matches than fit on the screen, only the first screenful is shown. The matches to insert into the command line can be selected from this list. In the list one match is highlighted using the value for ma from the ZLS_COLORS or ZLS_COLOURS parameter. The default value for this is `7' which forces the selected match to be highlighted using standout mode on a vt100-compatible terminal. If neither ZLS_COLORS nor ZLS_COLOURS is set, the same terminal control sequence as for the `%S' escape in prompts is used. If there are more matches than fit on the screen and the parameter MENUPROMPT is set, its value will be shown below the matches. It supports the same escape sequences as LISTPROMPT, but the number of the match or line shown will be that of the one where the mark is placed. If its value is the empty string, a default prompt will be used. The MENUSCROLL parameter can be used to specify how the list is scrolled. If the parameter is unset, this is done line by line, if it is set to `0' (zero), the list will scroll half the number of lines of the screen. If the value is positive, it gives the number of lines to scroll and if it is negative, the list will be scrolled the number of lines of the screen minus the (absolute) value. As for the ZLS_COLORS, ZLS_COLOURS and LISTPROMPT parameters, neither MENUPROMPT nor MENUSCROLL should be set directly when using the shell function based completion system. Instead, the select-prompt and select-scroll styles should be used. The completion code sometimes decides not to show all of the matches in the list. These hidden matches are either matches for which the completion function which added them explicitly requested that they not appear in the list (using the -n option of the compadd builtin command) or they are matches which duplicate a string already in the list (because they differ only in things like prefixes or suffixes that are not displayed). In the list used for menu selection, however, even these matches are shown so that it is possible to select them. To highlight such matches the hi and du capabilities in the ZLS_COLORS and ZLS_COLOURS parameters are supported for hidden matches of the first and second kind, respectively. Selecting matches is done by moving the mark around using the zle movement functions. When not all matches can be shown on the screen at the same time, the list will scroll up and down when crossing the top or bottom line. The following zle functions have special meaning during menu selection. Note that the following always perform the same task within the menu selection map and cannot be replaced by user defined widgets, nor can the set of functions be extended: accept-line, accept-search accept the current match and leave menu selection (but do not cause the command line to be accepted) send-break leaves menu selection and restores the previous contents of the command line redisplay, clear-screen execute their normal function without leaving menu selection accept-and-hold, accept-and-menu-complete accept the currently inserted match and continue selection allowing to select the next match to insert into the line accept-and-infer-next-history accepts the current match and then tries completion with menu selection again; in the case of files this allows one to select a directory and immediately attempt to complete files in it; if there are no matches, a message is shown and one can use undo to go back to completion on the previous level, every other key leaves menu selection (including the other zle functions which are otherwise special during menu selection) undo removes matches inserted during the menu selection by one of the three functions before down-history, down-line-or-history vi-down-line-or-history, down-line-or-search moves the mark one line down up-history, up-line-or-history vi-up-line-or-history, up-line-or-search moves the mark one line up forward-char, vi-forward-char moves the mark one column right backward-char, vi-backward-char moves the mark one column left forward-word, vi-forward-word vi-forward-word-end, emacs-forward-word moves the mark one screenful down backward-word, vi-backward-word, emacs-backward-word moves the mark one screenful up vi-forward-blank-word, vi-forward-blank-word-end moves the mark to the first line of the next group of matches vi-backward-blank-word moves the mark to the last line of the previous group of matches beginning-of-history moves the mark to the first line end-of-history moves the mark to the last line beginning-of-buffer-or-history, beginning-of-line beginning-of-line-hist, vi-beginning-of-line moves the mark to the leftmost column end-of-buffer-or-history, end-of-line end-of-line-hist, vi-end-of-line moves the mark to the rightmost column complete-word, menu-complete, expand-or-complete expand-or-complete-prefix, menu-expand-or-complete moves the mark to the next match reverse-menu-complete moves the mark to the previous match vi-insert this toggles between normal and interactive mode; in interactive mode the keys bound to self-insert and self-insert-unmeta insert into the command line as in normal editing mode but without leaving menu selection; after each character completion is tried again and the list changes to contain only the new matches; the completion widgets make the longest unambiguous string be inserted in the command line and undo and backward-delete-char go back to the previous set of matches history-incremental-search-forward history-incremental-search-backward this starts incremental searches in the list of completions displayed; in this mode, accept-line only leaves incremental search, going back to the normal menu selection mode All movement functions wrap around at the edges; any other zle function not listed leaves menu selection and executes that function. It is possible to make widgets in the above list do the same by using the form of the widget with a `.' in front. For example, the widget `.accept-line' has the effect of leaving menu selection and accepting the entire command line. During this selection the widget uses the keymap menuselect. Any key that is not defined in this keymap or that is bound to undefined-key is looked up in the keymap currently selected. This is used to ensure that the most important keys used during selection (namely the cursor keys, return, and TAB) have sensible defaults. However, keys in the menuselect keymap can be modified directly using the bindkey builtin command (see *Note The zsh/zle Module::). For example, to make the return key leave menu selection without accepting the match currently selected one could call bindkey -M menuselect '^M' send-break after loading the zsh/complist module.  File: zsh.info, Node: The zsh/computil Module, Next: The zsh/curses Module, Prev: The zsh/complist Module, Up: Zsh Modules 22.8 The zsh/computil Module ============================ The zsh/computil module adds several builtin commands that are used by some of the completion functions in the completion system based on shell functions (see *Note Completion System:: ). Except for compquote these builtin commands are very specialised and thus not very interesting when writing your own completion functions. In summary, these builtin commands are: comparguments This is used by the _arguments function to do the argument and command line parsing. Like compdescribe it has an option -i to do the parsing and initialize some internal state and various options to access the state information to decide what should be completed. compdescribe This is used by the _describe function to build the displays for the matches and to get the strings to add as matches with their options. On the first call one of the options -i or -I should be supplied as the first argument. In the first case, display strings without the descriptions will be generated, in the second case, the string used to separate the matches from their descriptions must be given as the second argument and the descriptions (if any) will be shown. All other arguments are like the definition arguments to _describe itself. Once compdescribe has been called with either the -i or the -I option, it can be repeatedly called with the -g option and the names of four parameters as its arguments. This will step through the different sets of matches and store the value of compstate[list] in the first scalar, the options for compadd in the second array, the matches in the third array, and the strings to be displayed in the completion listing in the fourth array. The arrays may then be directly given to compadd to register the matches with the completion code. compfiles Used by the _path_files function to optimize complex recursive filename generation (globbing). It does three things. With the -p and -P options it builds the glob patterns to use, including the paths already handled and trying to optimize the patterns with respect to the prefix and suffix from the line and the match specification currently used. The -i option does the directory tests for the ignore-parents style and the -r option tests if a component for some of the matches are equal to the string on the line and removes all other matches if that is true. compgroups Used by the _tags function to implement the internals of the group-order style. This only takes its arguments as names of completion groups and creates the groups for it (all six types: sorted and unsorted, both without removing duplicates, with removing all duplicates and with removing consecutive duplicates). compquote [ -p ] NAMES ... There may be reasons to write completion functions that have to add the matches using the -Q option to compadd and perform quoting themselves. Instead of interpreting the first character of the all_quotes key of the compstate special association and using the q flag for parameter expansions, one can use this builtin command. The arguments are the names of scalar or array parameters and the values of these parameters are quoted as needed for the innermost quoting level. If the -p option is given, quoting is done as if there is some prefix before the values of the parameters, so that a leading equal sign will not be quoted. The return status is non-zero in case of an error and zero otherwise. comptags comptry These implement the internals of the tags mechanism. compvalues Like comparguments, but for the _values function.  File: zsh.info, Node: The zsh/curses Module, Next: The zsh/datetime Module, Prev: The zsh/computil Module, Up: Zsh Modules 22.9 The zsh/curses Module ========================== The zsh/curses module makes available one builtin command and various parameters. 22.9.1 Builtin -------------- zcurses init zcurses end zcurses addwin TARGETWIN NLINES NCOLS BEGIN_Y BEGIN_X [ PARENTWIN ] zcurses delwin TARGETWIN zcurses refresh [ TARGETWIN ... ] zcurses touch TARGETWIN ... zcurses move TARGETWIN NEW_Y NEW_X zcurses clear TARGETWIN [ redraw | eol | bot ] zcurses position TARGETWIN ARRAY zcurses char TARGETWIN CHARACTER zcurses string TARGETWIN STRING zcurses border TARGETWIN BORDER zcurses attr TARGETWIN [ [+|-]ATTRIBUTE | FG_COL/BG_COL ] [...] zcurses bg TARGETWIN [ [+|-]ATTRIBUTE | FG_COL/BG_COL | @CHAR ] [...] zcurses scroll TARGETWIN [ on | off | [+|-]LINES ] zcurses input TARGETWIN [ PARAM [ KPARAM [ MPARAM ] ] ] zcurses mouse [ delay NUM | [+|-]motion ] zcurses timeout TARGETWIN INTVAL zcurses querychar TARGETWIN [ PARAM ] zcurses resize HEIGHT WIDTH [ endwin | nosave | endwin_nosave ] Manipulate curses windows. All uses of this command should be bracketed by `zcurses init' to initialise use of curses, and `zcurses end' to end it; omitting `zcurses end' can cause the terminal to be in an unwanted state. The subcommand addwin creates a window with NLINES lines and NCOLS columns. Its upper left corner will be placed at row BEGIN_Y and column BEGIN_X of the screen. TARGETWIN is a string and refers to the name of a window that is not currently assigned. Note in particular the curses convention that vertical values appear before horizontal values. If addwin is given an existing window as the final argument, the new window is created as a subwindow of PARENTWIN. This differs from an ordinary new window in that the memory of the window contents is shared with the parent's memory. Subwindows must be deleted before their parent. Note that the coordinates of subwindows are relative to the screen, not the parent, as with other windows. Use the subcommand delwin to delete a window created with addwin. Note that end does _not_ implicitly delete windows, and that delwin does not erase the screen image of the window. The window corresponding to the full visible screen is called stdscr; it always exists after `zcurses init' and cannot be delete with delwin. The subcommand refresh will refresh window TARGETWIN; this is necessary to make any pending changes (such as characters you have prepared for output with char) visible on the screen. refresh without an argument causes the screen to be cleared and redrawn. If multiple windows are given, the screen is updated once at the end. The subcommand touch marks the TARGETWINs listed as changed. This is necessary before refreshing windows if a window that was in front of another window (which may be stdscr) is deleted. The subcommand move moves the cursor position in TARGETWIN to new coordinates NEW_Y and NEW_X. Note that the subcommand string (but not the subcommand char) advances the cursor position over the characters added. The subcommand clear erases the contents of TARGETWIN. One (and no more than one) of three options may be specified. With the option redraw, in addition the next refresh of TARGETWIN will cause the screen to be cleared and repainted. With the option eol, TARGETWIN is only cleared to the end of the current cursor line. With the option bot, TARGETWIN is cleared to the end of the window, i.e everything to the right and below the cursor is cleared. The subcommand position writes various positions associated with TARGETWIN into the array named ARRAY. These are, in order: - The y and x coordinates of the cursor relative to the top left of TARGETWIN - The y and x coordinates of the top left of TARGETWIN on the screen - The size of TARGETWIN in y and x dimensions. Outputting characters and strings are achieved by char and string respectively. To draw a border around window TARGETWIN, use border. Note that the border is not subsequently handled specially: in other words, the border is simply a set of characters output at the edge of the window. Hence it can be overwritten, can scroll off the window, etc. The subcommand attr will set TARGETWIN's attributes or foreground/background color pair for any successive character output. Each ATTRIBUTE given on the line may be prepended by a + to set or a - to unset that attribute; + is assumed if absent. The attributes supported are blink, bold, dim, reverse, standout, and underline. Each FG_COL/BG_COL attribute (to be read as `FG_COL on BG_COL') sets the foreground and background color for character output. The color default is sometimes available (in particular if the library is ncurses), specifying the foreground or background color with which the terminal started. The color pair default/default is always available. To use more than the 8 named colors (red, green, etc.) construct the FG_COL/BG_COL pairs where FG_COL and BG_COL are decimal integers, e.g 128/200. The maximum color value is 254 if the terminal supports 256 colors. bg overrides the color and other attributes of all characters in the window. Its usual use is to set the background initially, but it will overwrite the attributes of any characters at the time when it is called. In addition to the arguments allowed with attr, an argument @CHAR specifies a character to be shown in otherwise blank areas of the window. Owing to limitations of curses this cannot be a multibyte character (use of ASCII characters only is recommended). As the specified set of attributes override the existing background, turning attributes off in the arguments is not useful, though this does not cause an error. The subcommand scroll can be used with on or off to enabled or disable scrolling of a window when the cursor would otherwise move below the window due to typing or output. It can also be used with a positive or negative integer to scroll the window up or down the given number of lines without changing the current cursor position (which therefore appears to move in the opposite direction relative to the window). In the second case, if scrolling is off it is temporarily turned on to allow the window to be scrolled. The subcommand input reads a single character from the window without echoing it back. If PARAM is supplied the character is assigned to the parameter PARAM, else it is assigned to the parameter REPLY. If both PARAM and KPARAM are supplied, the key is read in `keypad' mode. In this mode special keys such as function keys and arrow keys return the name of the key in the parameter KPARAM. The key names are the macros defined in the curses.h or ncurses.h with the prefix `KEY_' removed; see also the description of the parameter zcurses_keycodes below. Other keys cause a value to be set in PARAM as before. On a successful return only one of PARAM or KPARAM contains a non-empty string; the other is set to an empty string. If MPARAM is also supplied, input attempts to handle mouse input. This is only available with the ncurses library; mouse handling can be detected by checking for the exit status of `zcurses mouse' with no arguments. If a mouse button is clicked (or double- or triple-clicked, or pressed or released with a configurable delay from being clicked) then kparam is set to the string MOUSE, and MPARAM is set to an array consisting of the following elements: - An identifier to discriminate different input devices; this is only rarely useful. - The x, y and z coordinates of the mouse click relative to the full screen, as three elements in that order (i.e. the y coordinate is, unusually, after the x coordinate). The z coordinate is only available for a few unusual input devices and is otherwise set to zero. - Any events that occurred as separate items; usually there will be just one. An event consists of PRESSED, RELEASED, CLICKED, DOUBLE_CLICKED or TRIPLE_CLICKED followed immediately (in the same element) by the number of the button. - If the shift key was pressed, the string SHIFT. - If the control key was pressed, the string CTRL. - If the alt key was pressed, the string ALT. Not all mouse events may be passed through to the terminal window; most terminal emulators handle some mouse events themselves. Note that the ncurses manual implies that using input both with and without mouse handling may cause the mouse cursor to appear and disappear. The subcommand mouse can be used to configure the use of the mouse. There is no window argument; mouse options are global. `zcurses mouse' with no arguments returns status 0 if mouse handling is possible, else status 1. Otherwise, the possible arguments (which may be combined on the same command line) are as follows. delay NUM sets the maximum delay in milliseconds between press and release events to be considered as a click; the value 0 disables click resolution, and the default is one sixth of a second. motion proceeded by an optional `+' (the default) or - turns on or off reporting of mouse motion in addition to clicks, presses and releases, which are always reported. However, it appears reports for mouse motion are not currently implemented. The subcommand timeout specifies a timeout value for input from TARGETWIN. If INTVAL is negative, `zcurses input' waits indefinitely for a character to be typed; this is the default. If INTVAL is zero, `zcurses input' returns immediately; if there is typeahead it is returned, else no input is done and status 1 is returned. If INTVAL is positive, `zcurses input' waits INTVAL milliseconds for input and if there is none at the end of that period returns status 1. The subcommand querychar queries the character at the current cursor position. The return values are stored in the array named PARAM if supplied, else in the array reply. The first value is the character (which may be a multibyte character if the system supports them); the second is the color pair in the usual FG_COL/BG_COL notation, or 0 if color is not supported. Any attributes other than color that apply to the character, as set with the subcommand attr, appear as additional elements. The subcommand resize resizes stdscr and all windows to given dimensions (windows that stick out from the new dimensions are resized down). The underlying curses extension (resize_term call) can be unavailable. To verify, zeroes can be used for HEIGHT and WIDTH. If the result of the subcommand is 0, resize_term is available (2 otherwise). Tests show that resizing can be normally accomplished by calling zcurses end and zcurses refresh. The resize subcommand is provided for versatility. Multiple system configurations have been checked and zcurses end and zcurses refresh are still needed for correct terminal state after resize. To invoke them with resize, use ENDWIN argument. Using NOSAVE argument will cause new terminal state to not be saved internally by zcurses. This is also provided for versatility and should normally be not needed. 22.9.2 Parameters ----------------- ZCURSES_COLORS Readonly integer. The maximum number of colors the terminal supports. This value is initialised by the curses library and is not available until the first time zcurses init is run. ZCURSES_COLOR_PAIRS Readonly integer. The maximum number of color pairs FG_COL/BG_COL that may be defined in `zcurses attr' commands; note this limit applies to all color pairs that have been used whether or not they are currently active. This value is initialised by the curses library and is not available until the first time zcurses init is run. zcurses_attrs Readonly array. The attributes supported by zsh/curses; available as soon as the module is loaded. zcurses_colors Readonly array. The colors supported by zsh/curses; available as soon as the module is loaded. zcurses_keycodes Readonly array. The values that may be returned in the second parameter supplied to `zcurses input' in the order in which they are defined internally by curses. Not all function keys are listed, only F0; curses reserves space for F0 up to F63. zcurses_windows Readonly array. The current list of windows, i.e. all windows that have been created with `zcurses addwin' and not removed with `zcurses delwin'.  File: zsh.info, Node: The zsh/datetime Module, Next: The zsh/db/gdbm Module, Prev: The zsh/curses Module, Up: Zsh Modules 22.10 The zsh/datetime Module ============================= The zsh/datetime module makes available one builtin command: strftime [ -s SCALAR ] FORMAT [ EPOCHTIME [ NANOSECONDS ] ] strftime -r [ -q ] [ -s SCALAR ] FORMAT TIMESTRING Output the date in the FORMAT specified. With no EPOCHTIME, the current system date/time is used; optionally, EPOCHTIME may be used to specify the number of seconds since the epoch, and NANOSECONDS may additionally be used to specify the number of nanoseconds past the second (otherwise that number is assumed to be 0). See man page strftime(3) for details. The zsh extensions described in *Note Prompt Expansion:: are also available. -q Run quietly; suppress printing of all error messages described below. Errors for invalid EPOCHTIME values are always printed. -r With the option -r (reverse), use FORMAT to parse the input string TIMESTRING and output the number of seconds since the epoch at which the time occurred. The parsing is implemented by the system function strptime; see man page strptime(3). This means that zsh format extensions are not available, but for reverse lookup they are not required. In most implementations of strftime any timezone in the TIMESTRING is ignored and the local timezone declared by the TZ environment variable is used; other parameters are set to zero if not present. If TIMESTRING does not match FORMAT the command returns status 1 and prints an error message. If TIMESTRING matches FORMAT but not all characters in TIMESTRING were used, the conversion succeeds but also prints an error message. If either of the system functions strptime or mktime is not available, status 2 is returned and an error message is printed. -s SCALAR Assign the date string (or epoch time in seconds if -r is given) to SCALAR instead of printing it. Note that depending on the system's declared integral time type, strftime may produce incorrect results for epoch times greater than 2147483647 which corresponds to 2038-01-19 03:14:07 +0000. The zsh/datetime module makes available several parameters; all are readonly: EPOCHREALTIME A floating point value representing the number of seconds since the epoch. The notional accuracy is to nanoseconds if the clock_gettime call is available and to microseconds otherwise, but in practice the range of double precision floating point and shell scheduling latencies may be significant effects. EPOCHSECONDS An integer value representing the number of seconds since the epoch. epochtime An array value containing the number of seconds since the epoch in the first element and the remainder of the time since the epoch in nanoseconds in the second element. To ensure the two elements are consistent the array should be copied or otherwise referenced as a single substitution before the values are used. The following idiom may be used: for secs nsecs in $epochtime; do ... done  File: zsh.info, Node: The zsh/db/gdbm Module, Next: The zsh/deltochar Module, Prev: The zsh/datetime Module, Up: Zsh Modules 22.11 The zsh/db/gdbm Module ============================ The zsh/db/gdbm module is used to create "tied" associative arrays that interface to database files. If the GDBM interface is not available, the builtins defined by this module will report an error. This module is also intended as a prototype for creating additional database interfaces, so the ztie builtin may move to a more generic module in the future. The builtins in this module are: ztie -d db/gdbm -f FILENAME [ -r ] ARRAYNAME Open the GDBM database identified by FILENAME and, if successful, create the associative array ARRAYNAME linked to the file. To create a local tied array, the parameter must first be declared, so commands similar to the following would be executed inside a function scope: local -A sampledb ztie -d db/gdbm -f sample.gdbm sampledb The -r option opens the database file for reading only, creating a parameter with the readonly attribute. Without this option, using `ztie' on a file for which the user does not have write permission is an error. If writable, the database is opened synchronously so fields changed in ARRAYNAME are immediately written to FILENAME. Changes to the file modes FILENAME after it has been opened do not alter the state of ARRAYNAME, but `typeset -r ARRAYNAME' works as expected. zuntie [ -u ] ARRAYNAME ... Close the GDBM database associated with each ARRAYNAME and then unset the parameter. The -u option forces an unset of parameters made readonly with `ztie -r'. This happens automatically if the parameter is explicitly unset or its local scope (function) ends. Note that a readonly parameter may not be explicitly unset, so the only way to unset a global parameter created with `ztie -r' is to use `zuntie -u'. zgdbmpath PARAMETERNAME Put path to database file assigned to PARAMETERNAME into REPLY scalar. zgdbm_tied Array holding names of all tied parameters. The fields of an associative array tied to GDBM are neither cached nor otherwise stored in memory, they are read from or written to the database on each reference. Thus, for example, the values in a readonly array may be changed by a second writer of the same database file.  File: zsh.info, Node: The zsh/deltochar Module, Next: The zsh/example Module, Prev: The zsh/db/gdbm Module, Up: Zsh Modules 22.12 The zsh/deltochar Module ============================== The zsh/deltochar module makes available two ZLE functions: delete-to-char Read a character from the keyboard, and delete from the cursor position up to and including the next (or, with repeat count N, the Nth) instance of that character. Negative repeat counts mean delete backwards. zap-to-char This behaves like delete-to-char, except that the final occurrence of the character itself is not deleted.  File: zsh.info, Node: The zsh/example Module, Next: The zsh/files Module, Prev: The zsh/deltochar Module, Up: Zsh Modules 22.13 The zsh/example Module ============================ The zsh/example module makes available one builtin command: example [ -flags ] [ ARGS ... ] Displays the flags and arguments it is invoked with. The purpose of the module is to serve as an example of how to write a module.  File: zsh.info, Node: The zsh/files Module, Next: The zsh/langinfo Module, Prev: The zsh/example Module, Up: Zsh Modules 22.14 The zsh/files Module ========================== The zsh/files module makes available some common commands for file manipulation as builtins; these commands are probably not needed for many normal situations but can be useful in emergency recovery situations with constrained resources. The commands do not implement all features now required by relevant standards committees. For all commands, a variant beginning zf_ is also available and loaded automatically. Using the features capability of zmodload will let you load only those names you want. Note that it's possible to load only the builtins with zsh-specific names using the following command: zmodload -m -F zsh/files b:zf_\* The commands loaded by default are: chgrp [ -hRs ] GROUP FILENAME ... Changes group of files specified. This is equivalent to chown with a USER-SPEC argument of `:GROUP'. chmod [ -Rs ] MODE FILENAME ... Changes mode of files specified. The specified MODE must be in octal. The -R option causes chmod to recursively descend into directories, changing the mode of all files in the directory after changing the mode of the directory itself. The -s option is a zsh extension to chmod functionality. It enables paranoid behaviour, intended to avoid security problems involving a chmod being tricked into affecting files other than the ones intended. It will refuse to follow symbolic links, so that (for example) ``chmod 600 /tmp/foo/passwd'' can't accidentally chmod /etc/passwd if /tmp/foo happens to be a link to /etc. It will also check where it is after leaving directories, so that a recursive chmod of a deep directory tree can't end up recursively chmoding /usr as a result of directories being moved up the tree. chown [ -hRs ] USER-SPEC FILENAME ... Changes ownership and group of files specified. The USER-SPEC can be in four forms: USER change owner to USER; do not change group USER:: change owner to USER; do not change group USER: change owner to USER; change group to USER's primary group USER:GROUP change owner to USER; change group to GROUP :GROUP do not change owner; change group to GROUP In each case, the `:' may instead be a `.'. The rule is that if there is a `:' then the separator is `:', otherwise if there is a `.' then the separator is `.', otherwise there is no separator. Each of USER and GROUP may be either a username (or group name, as appropriate) or a decimal user ID (group ID). Interpretation as a name takes precedence, if there is an all-numeric username (or group name). If the target is a symbolic link, the -h option causes chown to set the ownership of the link instead of its target. The -R option causes chown to recursively descend into directories, changing the ownership of all files in the directory after changing the ownership of the directory itself. The -s option is a zsh extension to chown functionality. It enables paranoid behaviour, intended to avoid security problems involving a chown being tricked into affecting files other than the ones intended. It will refuse to follow symbolic links, so that (for example) ``chown luser /tmp/foo/passwd'' can't accidentally chown /etc/passwd if /tmp/foo happens to be a link to /etc. It will also check where it is after leaving directories, so that a recursive chown of a deep directory tree can't end up recursively chowning /usr as a result of directories being moved up the tree. ln [ -dfhins ] FILENAME DEST ln [ -dfhins ] FILENAME ... DIR Creates hard (or, with -s, symbolic) links. In the first form, the specified DESTination is created, as a link to the specified FILENAME. In the second form, each of the FILENAMEs is taken in turn, and linked to a pathname in the specified DIRectory that has the same last pathname component. Normally, ln will not attempt to create hard links to directories. This check can be overridden using the -d option. Typically only the super-user can actually succeed in creating hard links to directories. This does not apply to symbolic links in any case. By default, existing files cannot be replaced by links. The -i option causes the user to be queried about replacing existing files. The -f option causes existing files to be silently deleted, without querying. -f takes precedence. The -h and -n options are identical and both exist for compatibility; either one indicates that if the target is a symlink then it should not be dereferenced. Typically this is used in combination with -sf so that if an existing link points to a directory then it will be removed, instead of followed. If this option is used with multiple filenames and the target is a symbolic link pointing to a directory then the result is an error. mkdir [ -p ] [ -m MODE ] DIR ... Creates directories. With the -p option, non-existing parent directories are first created if necessary, and there will be no complaint if the directory already exists. The -m option can be used to specify (in octal) a set of file permissions for the created directories, otherwise mode 777 modified by the current umask (see man page umask(2)) is used. mv [ -fi ] FILENAME DEST mv [ -fi ] FILENAME ... DIR Moves files. In the first form, the specified FILENAME is moved to the specified DESTination. In the second form, each of the FILENAMEs is taken in turn, and moved to a pathname in the specified DIRectory that has the same last pathname component. By default, the user will be queried before replacing any file that the user cannot write to, but writable files will be silently removed. The -i option causes the user to be queried about replacing any existing files. The -f option causes any existing files to be silently deleted, without querying. -f takes precedence. Note that this mv will not move files across devices. Historical versions of mv, when actual renaming is impossible, fall back on copying and removing files; if this behaviour is desired, use cp and rm manually. This may change in a future version. rm [ -dfiRrs ] FILENAME ... Removes files and directories specified. Normally, rm will not remove directories (except with the -R or -r options). The -d option causes rm to try removing directories with unlink (see man page unlink(2)), the same method used for files. Typically only the super-user can actually succeed in unlinking directories in this way. -d takes precedence over -R and -r. By default, the user will be queried before removing any file that the user cannot write to, but writable files will be silently removed. The -i option causes the user to be queried about removing any files. The -f option causes files to be silently deleted, without querying, and suppresses all error indications. -f takes precedence. The -R and -r options cause rm to recursively descend into directories, deleting all files in the directory before removing the directory with the rmdir system call (see man page rmdir(2)). The -s option is a zsh extension to rm functionality. It enables paranoid behaviour, intended to avoid common security problems involving a root-run rm being tricked into removing files other than the ones intended. It will refuse to follow symbolic links, so that (for example) ``rm /tmp/foo/passwd'' can't accidentally remove /etc/passwd if /tmp/foo happens to be a link to /etc. It will also check where it is after leaving directories, so that a recursive removal of a deep directory tree can't end up recursively removing /usr as a result of directories being moved up the tree. rmdir DIR ... Removes empty directories specified. sync Calls the system call of the same name (see man page sync(2)), which flushes dirty buffers to disk. It might return before the I/O has actually been completed.  File: zsh.info, Node: The zsh/langinfo Module, Next: The zsh/mapfile Module, Prev: The zsh/files Module, Up: Zsh Modules 22.15 The zsh/langinfo Module ============================= The zsh/langinfo module makes available one parameter: langinfo An associative array that maps langinfo elements to their values. Your implementation may support a number of the following keys: CODESET, D_T_FMT, D_FMT, T_FMT, RADIXCHAR, THOUSEP, YESEXPR, NOEXPR, CRNCYSTR, ABDAY_{1..7}, DAY_{1..7}, ABMON_{1..12}, MON_{1..12}, T_FMT_AMPM, AM_STR, PM_STR, ERA, ERA_D_FMT, ERA_D_T_FMT, ERA_T_FMT, ALT_DIGITS  File: zsh.info, Node: The zsh/mapfile Module, Next: The zsh/mathfunc Module, Prev: The zsh/langinfo Module, Up: Zsh Modules 22.16 The zsh/mapfile Module ============================ The zsh/mapfile module provides one special associative array parameter of the same name. mapfile This associative array takes as keys the names of files; the resulting value is the content of the file. The value is treated identically to any other text coming from a parameter. The value may also be assigned to, in which case the file in question is written (whether or not it originally existed); or an element may be unset, which will delete the file in question. For example, `vared mapfile[myfile]' works as expected, editing the file `myfile'. When the array is accessed as a whole, the keys are the names of files in the current directory, and the values are empty (to save a huge overhead in memory). Thus ${(k)mapfile} has the same effect as the glob operator *(D), since files beginning with a dot are not special. Care must be taken with expressions such as rm ${(k)mapfile}, which will delete every file in the current directory without the usual `rm *' test. The parameter mapfile may be made read-only; in that case, files referenced may not be written or deleted. A file may conveniently be read into an array as one line per element with the form `ARRAY=("${(f@)mapfile[FILENAME]}")'. The double quotes and the `@' are necessary to prevent empty lines from being removed. Note that if the file ends with a newline, the shell will split on the final newline, generating an additional empty field; this can be suppressed by using `ARRAY=("${(f@)${mapfile[FILENAME]%$'\n'}}")'. 22.16.1 Limitations ------------------- Although reading and writing of the file in question is efficiently handled, zsh's internal memory management may be arbitrarily baroque; however, mapfile is usually very much more efficient than anything involving a loop. Note in particular that the whole contents of the file will always reside physically in memory when accessed (possibly multiple times, due to standard parameter substitution operations). In particular, this means handling of sufficiently long files (greater than the machine's swap space, or than the range of the pointer type) will be incorrect. No errors are printed or flagged for non-existent, unreadable, or unwritable files, as the parameter mechanism is too low in the shell execution hierarchy to make this convenient. It is unfortunate that the mechanism for loading modules does not yet allow the user to specify the name of the shell parameter to be given the special behaviour.  File: zsh.info, Node: The zsh/mathfunc Module, Next: The zsh/nearcolor Module, Prev: The zsh/mapfile Module, Up: Zsh Modules 22.17 The zsh/mathfunc Module ============================= The zsh/mathfunc module provides standard mathematical functions for use when evaluating mathematical formulae. The syntax agrees with normal C and FORTRAN conventions, for example, (( f = sin(0.3) )) assigns the sine of 0.3 to the parameter f. Most functions take floating point arguments and return a floating point value. However, any necessary conversions from or to integer type will be performed automatically by the shell. Apart from atan with a second argument and the abs, int and float functions, all functions behave as noted in the manual page for the corresponding C function, except that any arguments out of range for the function in question will be detected by the shell and an error reported. The following functions take a single floating point argument: acos, acosh, asin, asinh, atan, atanh, cbrt, ceil, cos, cosh, erf, erfc, exp, expm1, fabs, floor, gamma, j0, j1, lgamma, log, log10, log1p, log2, logb, sin, sinh, sqrt, tan, tanh, y0, y1. The atan function can optionally take a second argument, in which case it behaves like the C function atan2. The ilogb function takes a single floating point argument, but returns an integer. The function signgam takes no arguments, and returns an integer, which is the C variable of the same name, as described in man page gamma(3). Note that it is therefore only useful immediately after a call to gamma or lgamma. Note also that `signgam()' and `signgam' are distinct expressions. The functions min, max, and sum are defined not in this module but in the zmathfunc autoloadable function, described in *Note Mathematical Functions::. The following functions take two floating point arguments: copysign, fmod, hypot, nextafter. The following take an integer first argument and a floating point second argument: jn, yn. The following take a floating point first argument and an integer second argument: ldexp, scalb. The function abs does not convert the type of its single argument; it returns the absolute value of either a floating point number or an integer. The functions float and int convert their arguments into a floating point or integer value (by truncation) respectively. Note that the C pow function is available in ordinary math evaluation as the `**' operator and is not provided here. The function rand48 is available if your system's mathematical library has the function erand48(3). It returns a pseudo-random floating point number between 0 and 1. It takes a single string optional argument. If the argument is not present, the random number seed is initialised by three calls to the rand(3) function -- this produces the same random numbers as the next three values of $RANDOM. If the argument is present, it gives the name of a scalar parameter where the current random number seed will be stored. On the first call, the value must contain at least twelve hexadecimal digits (the remainder of the string is ignored), or the seed will be initialised in the same manner as for a call to rand48 with no argument. Subsequent calls to rand48(PARAM) will then maintain the seed in the parameter PARAM as a string of twelve hexadecimal digits, with no base signifier. The random number sequences for different parameters are completely independent, and are also independent from that used by calls to rand48 with no argument. For example, consider print $(( rand48(seed) )) print $(( rand48() )) print $(( rand48(seed) )) Assuming $seed does not exist, it will be initialised by the first call. In the second call, the default seed is initialised; note, however, that because of the properties of rand() there is a correlation between the seeds used for the two initialisations, so for more secure uses, you should generate your own 12-byte seed. The third call returns to the same sequence of random numbers used in the first call, unaffected by the intervening rand48().  File: zsh.info, Node: The zsh/nearcolor Module, Next: The zsh/newuser Module, Prev: The zsh/mathfunc Module, Up: Zsh Modules 22.18 The zsh/nearcolor Module ============================== The zsh/nearcolor module replaces colours specified as hex triplets with the nearest colour in the 88 or 256 colour palettes that are widely used by terminal emulators. By default, 24-bit true colour escape codes are generated when colours are specified using hex triplets. These are not supported by all terminals. The purpose of this module is to make it easier to define colour preferences in a form that can work across a range of terminal emulators. Aside from the default colour, the ANSI standard for terminal escape codes provides for eight colours. The bright attribute brings this to sixteen. These basic colours are commonly used in terminal applications due to being widely supported. Expanded 88 and 256 colour palettes are also common and, while the first sixteen colours vary somewhat between terminals and configurations, these add a generally consistent and predictable set of colours. In order to use the zsh/nearcolor module, it only needs to be loaded. Thereafter, whenever a colour is specified using a hex triplet, it will be compared against each of the available colours and the closest will be selected. The first sixteen colours are never matched in this process due to being unpredictable. It isn't possible to reliably detect support for true colour in the terminal emulator. It is therefore recommended to be selective in loading the zsh/nearcolor module. For example, the following checks the COLORTERM environment variable: [[ $COLORTERM = *(24bit|truecolor)* ]] || zmodload zsh/nearcolor Note that some terminals accept the true color escape codes but map them internally to a more limited palette in a similar manner to the zsh/nearcolor module.  File: zsh.info, Node: The zsh/newuser Module, Next: The zsh/parameter Module, Prev: The zsh/nearcolor Module, Up: Zsh Modules 22.19 The zsh/newuser Module ============================ The zsh/newuser module is loaded at boot if it is available, the RCS option is set, and the PRIVILEGED option is not set (all three are true by default). This takes place immediately after commands in the global zshenv file (typically /etc/zshenv), if any, have been executed. If the module is not available it is silently ignored by the shell; the module may safely be removed from $MODULE_PATH by the administrator if it is not required. On loading, the module tests if any of the start-up files .zshenv, .zprofile, .zshrc or .zlogin exist in the directory given by the environment variable ZDOTDIR, or the user's home directory if that is not set. The test is not performed and the module halts processing if the shell was in an emulation mode (i.e. had been invoked as some other shell than zsh). If none of the start-up files were found, the module then looks for the file newuser first in a sitewide directory, usually the parent directory of the site-functions directory, and if that is not found the module searches in a version-specific directory, usually the parent of the functions directory containing version-specific functions. (These directories can be configured when zsh is built using the -enable-site-scriptdir=DIR and -enable-scriptdir=DIR flags to configure, respectively; the defaults are PREFIX/share/zsh and PREFIX/share/zsh/$ZSH_VERSION where the default PREFIX is /usr/local.) If the file newuser is found, it is then sourced in the same manner as a start-up file. The file is expected to contain code to install start-up files for the user, however any valid shell code will be executed. The zsh/newuser module is then unconditionally unloaded. Note that it is possible to achieve exactly the same effect as the zsh/newuser module by adding code to /etc/zshenv. The module exists simply to allow the shell to make arrangements for new users without the need for intervention by package maintainers and system administrators. The script supplied with the module invokes the shell function zsh-newuser-install. This may be invoked directly by the user even if the zsh/newuser module is disabled. Note, however, that if the module is not installed the function will not be installed either. The function is documented in *Note User Configuration Functions::.  File: zsh.info, Node: The zsh/parameter Module, Next: The zsh/pcre Module, Prev: The zsh/newuser Module, Up: Zsh Modules 22.20 The zsh/parameter Module ============================== The zsh/parameter module gives access to some of the internal hash tables used by the shell by defining some special parameters. options The keys for this associative array are the names of the options that can be set and unset using the setopt and unsetopt builtins. The value of each key is either the string on if the option is currently set, or the string off if the option is unset. Setting a key to one of these strings is like setting or unsetting the option, respectively. Unsetting a key in this array is like setting it to the value off. commands This array gives access to the command hash table. The keys are the names of external commands, the values are the pathnames of the files that would be executed when the command would be invoked. Setting a key in this array defines a new entry in this table in the same way as with the hash builtin. Unsetting a key as in `unset "commands[foo]"' removes the entry for the given key from the command hash table. functions This associative array maps names of enabled functions to their definitions. Setting a key in it is like defining a function with the name given by the key and the body given by the value. Unsetting a key removes the definition for the function named by the key. dis_functions Like functions but for disabled functions. functions_source This readonly associative array maps names of enabled functions to the name of the file containing the source of the function. For an autoloaded function that has already been loaded, or marked for autoload with an absolute path, or that has had its path resolved with `functions -r', this is the file found for autoloading, resolved to an absolute path. For a function defined within the body of a script or sourced file, this is the name of that file. In this case, this is the exact path originally used to that file, which may be a relative path. For any other function, including any defined at an interactive prompt or an autoload function whose path has not yet been resolved, this is the empty string. However, the hash element is reported as defined just so long as the function is present: the keys to this hash are the same as those to $functions. dis_functions_source Like functions_source but for disabled functions. builtins This associative array gives information about the builtin commands currently enabled. The keys are the names of the builtin commands and the values are either `undefined' for builtin commands that will automatically be loaded from a module if invoked or `defined' for builtin commands that are already loaded. dis_builtins Like builtins but for disabled builtin commands. reswords This array contains the enabled reserved words. dis_reswords Like reswords but for disabled reserved words. patchars This array contains the enabled pattern characters. dis_patchars Like patchars but for disabled pattern characters. aliases This maps the names of the regular aliases currently enabled to their expansions. dis_aliases Like aliases but for disabled regular aliases. galiases Like aliases, but for global aliases. dis_galiases Like galiases but for disabled global aliases. saliases Like raliases, but for suffix aliases. dis_saliases Like saliases but for disabled suffix aliases. parameters The keys in this associative array are the names of the parameters currently defined. The values are strings describing the type of the parameter, in the same format used by the t parameter flag, see *Note Parameter Expansion:: . Setting or unsetting keys in this array is not possible. modules An associative array giving information about modules. The keys are the names of the modules loaded, registered to be autoloaded, or aliased. The value says which state the named module is in and is one of the strings `loaded', `autoloaded', or `alias:NAME', where NAME is the name the module is aliased to. Setting or unsetting keys in this array is not possible. dirstack A normal array holding the elements of the directory stack. Note that the output of the dirs builtin command includes one more directory, the current working directory. history This associative array maps history event numbers to the full history lines. Although it is presented as an associative array, the array of all values (${history[@]}) is guaranteed to be returned in order from most recent to oldest history event, that is, by decreasing history event number. historywords A special array containing the words stored in the history. These also appear in most to least recent order. jobdirs This associative array maps job numbers to the directories from which the job was started (which may not be the current directory of the job). The keys of the associative arrays are usually valid job numbers, and these are the values output with, for example, ${(k)jobdirs}. Non-numeric job references may be used when looking up a value; for example, ${jobdirs[%+]} refers to the current job. jobtexts This associative array maps job numbers to the texts of the command lines that were used to start the jobs. Handling of the keys of the associative array is as described for jobdirs above. jobstates This associative array gives information about the states of the jobs currently known. The keys are the job numbers and the values are strings of the form `JOB-STATE:MARK:PID=STATE...'. The JOB-STATE gives the state the whole job is currently in, one of `running', `suspended', or `done'. The MARK is `+' for the current job, `-' for the previous job and empty otherwise. This is followed by one `:PID=STATE' for every process in the job. The PIDs are, of course, the process IDs and the STATE describes the state of that process. Handling of the keys of the associative array is as described for jobdirs above. nameddirs This associative array maps the names of named directories to the pathnames they stand for. userdirs This associative array maps user names to the pathnames of their home directories. usergroups This associative array maps names of system groups of which the current user is a member to the corresponding group identifiers. The contents are the same as the groups output by the id command. funcfiletrace This array contains the absolute line numbers and corresponding file names for the point where the current function, sourced file, or (if EVAL_LINENO is set) eval command was called. The array is of the same length as funcsourcetrace and functrace, but differs from funcsourcetrace in that the line and file are the point of call, not the point of definition, and differs from functrace in that all values are absolute line numbers in files, rather than relative to the start of a function, if any. funcsourcetrace This array contains the file names and line numbers of the points where the functions, sourced files, and (if EVAL_LINENO is set) eval commands currently being executed were defined. The line number is the line where the `function NAME' or `NAME ()' started. In the case of an autoloaded function the line number is reported as zero. The format of each element is FILENAME:LINENO. For functions autoloaded from a file in native zsh format, where only the body of the function occurs in the file, or for files that have been executed by the source or `.' builtins, the trace information is shown as FILENAME:0, since the entire file is the definition. The source file name is resolved to an absolute path when the function is loaded or the path to it otherwise resolved. Most users will be interested in the information in the funcfiletrace array instead. funcstack This array contains the names of the functions, sourced files, and (if EVAL_LINENO is set) eval commands. currently being executed. The first element is the name of the function using the parameter. The standard shell array zsh_eval_context can be used to determine the type of shell construct being executed at each depth: note, however, that is in the opposite order, with the most recent item last, and it is more detailed, for example including an entry for toplevel, the main shell code being executed either interactively or from a script, which is not present in $funcstack. functrace This array contains the names and line numbers of the callers corresponding to the functions currently being executed. The format of each element is NAME:LINENO. Callers are also shown for sourced files; the caller is the point where the source or `.' command was executed.  File: zsh.info, Node: The zsh/pcre Module, Next: The zsh/param/private Module, Prev: The zsh/parameter Module, Up: Zsh Modules 22.21 The zsh/pcre Module ========================= The zsh/pcre module makes some commands available as builtins: pcre_compile [ -aimxs ] PCRE Compiles a perl-compatible regular expression. Option -a will force the pattern to be anchored. Option -i will compile a case-insensitive pattern. Option -m will compile a multi-line pattern; that is, ^ and $ will match newlines within the pattern. Option -x will compile an extended pattern, wherein whitespace and # comments are ignored. Option -s makes the dot metacharacter match all characters, including those that indicate newline. pcre_study Studies the previously-compiled PCRE which may result in faster matching. pcre_match [ -v VAR ] [ -a ARR ] [ -n OFFSET ] [ -b ] STRING Returns successfully if string matches the previously-compiled PCRE. Upon successful match, if the expression captures substrings within parentheses, pcre_match will set the array match to those substrings, unless the -a option is given, in which case it will set the array ARR. Similarly, the variable MATCH will be set to the entire matched portion of the string, unless the -v option is given, in which case the variable VAR will be set. No variables are altered if there is no successful match. A -n option starts searching for a match from the byte OFFSET position in STRING. If the -b option is given, the variable ZPCRE_OP will be set to an offset pair string, representing the byte offset positions of the entire matched portion within the STRING. For example, a ZPCRE_OP set to "32 45" indicates that the matched portion began on byte offset 32 and ended on byte offset 44. Here, byte offset position 45 is the position directly after the matched portion. Keep in mind that the byte position isn't necessarily the same as the character position when UTF-8 characters are involved. Consequently, the byte offset positions are only to be relied on in the context of using them for subsequent searches on STRING, using an offset position as an argument to the -n option. This is mostly used to implement the "find all non-overlapping matches" functionality. A simple example of "find all non-overlapping matches": string="The following zip codes: 78884 90210 99513" pcre_compile -m "\d{5}" accum=() pcre_match -b -- $string while [[ $? -eq 0 ]] do b=($=ZPCRE_OP) accum+=$MATCH pcre_match -b -n $b[2] -- $string done print -l $accum The zsh/pcre module makes available the following test condition: EXPR -pcre-match PCRE Matches a string against a perl-compatible regular expression. For example, [[ "$text" -pcre-match ^d+$ ]] && print text variable contains only "d's". If the REMATCH_PCRE option is set, the =~ operator is equivalent to -pcre-match, and the NO_CASE_MATCH option may be used. Note that NO_CASE_MATCH never applies to the pcre_match builtin, instead use the -i switch of pcre_compile.  File: zsh.info, Node: The zsh/param/private Module, Next: The zsh/regex Module, Prev: The zsh/pcre Module, Up: Zsh Modules 22.22 The zsh/param/private Module ================================== The zsh/param/private module is used to create parameters whose scope is limited to the current function body, and _not_ to other functions called by the current function. This module provides a single autoloaded builtin: private [ {+|-}AHUahlprtux ] [ {+|-}EFLRZi [ N ] ] [ NAME[=VALUE] ... ] The private builtin accepts all the same options and arguments as local (*Note Shell Builtin Commands::) except for the `-T' option. Tied parameters may not be made private. If used at the top level (outside a function scope), private creates a normal parameter in the same manner as declare or typeset. A warning about this is printed if WARN_CREATE_GLOBAL is set (*Note Options::). Used inside a function scope, private creates a local parameter similar to one declared with local, except having special properties noted below. Special parameters which expose or manipulate internal shell state, such as ARGC, argv, COLUMNS, LINES, UID, EUID, IFS, PROMPT, RANDOM, SECONDS, etc., cannot be made private unless the `-h' option is used to hide the special meaning of the parameter. This may change in the future. As with other typeset equivalents, private is both a builtin and a reserved word, so arrays may be assigned with parenthesized word list NAME=(VALUE...) syntax. However, the reserved word `private' is not available until zsh/param/private is loaded, so care must be taken with order of execution and parsing for function definitions which use private. To compensate for this, the module also adds the option `-P' to the `local' builtin to declare private parameters. For example, this construction fails if zsh/param/private has not yet been loaded when `bad_declaration' is defined: bad_declaration() { zmodload zsh/param/private private array=( one two three ) } This construction works because local is already a keyword, and the module is loaded before the statement is executed: good_declaration() { zmodload zsh/param/private local -P array=( one two three ) } The following is usable in scripts but may have trouble with autoload: zmodload zsh/param/private iffy_declaration() { private array=( one two three ) } The private builtin may always be used with scalar assignments and for declarations without assignments. Parameters declared with private have the following properties: * Within the function body where it is declared, the parameter behaves as a local, except as noted above for tied or special parameters. * The type of a parameter declared private cannot be changed in the scope where it was declared, even if the parameter is unset. Thus an array cannot be assigned to a private scalar, etc. * Within any other function called by the declaring function, the private parameter does _NOT_ hide other parameters of the same name, so for example a global parameter of the same name is visible and may be assigned or unset. This includes calls to anonymous functions, although that may also change in the future. * An exported private remains in the environment of inner scopes but appears unset for the current shell in those scopes. Generally, exporting private parameters should be avoided. Note that this differs from the static scope defined by compiled languages derived from C, in that the a new call to the same function creates a new scope, i.e., the parameter is still associated with the call stack rather than with the function definition. It differs from ksh `typeset -S' because the syntax used to define the function has no bearing on whether the parameter scope is respected.  File: zsh.info, Node: The zsh/regex Module, Next: The zsh/sched Module, Prev: The zsh/param/private Module, Up: Zsh Modules 22.23 The zsh/regex Module ========================== The zsh/regex module makes available the following test condition: EXPR -regex-match REGEX Matches a string against a POSIX extended regular expression. On successful match, matched portion of the string will normally be placed in the MATCH variable. If there are any capturing parentheses within the regex, then the match array variable will contain those. If the match is not successful, then the variables will not be altered. For example, [[ alphabetical -regex-match ^a([^a]+)a([^a]+)a ]] && print -l $MATCH X $match If the option REMATCH_PCRE is not set, then the =~ operator will automatically load this module as needed and will invoke the -regex-match operator. If BASH_REMATCH is set, then the array BASH_REMATCH will be set instead of MATCH and match.  File: zsh.info, Node: The zsh/sched Module, Next: The zsh/net/socket Module, Prev: The zsh/regex Module, Up: Zsh Modules 22.24 The zsh/sched Module ========================== The zsh/sched module makes available one builtin command and one parameter. sched [-o] [+]HH:MM[:SS] COMMAND ... sched [-o] [+]SECONDS COMMAND ... sched [ -ITEM ] Make an entry in the scheduled list of commands to execute. The time may be specified in either absolute or relative time, and either as hours, minutes and (optionally) seconds separated by a colon, or seconds alone. An absolute number of seconds indicates the time since the epoch (1970/01/01 00:00); this is useful in combination with the features in the zsh/datetime module, see *Note The zsh/datetime Module::. With no arguments, prints the list of scheduled commands. If the scheduled command has the -o flag set, this is shown at the start of the command. With the argument `-ITEM', removes the given item from the list. The numbering of the list is continuous and entries are in time order, so the numbering can change when entries are added or deleted. Commands are executed either immediately before a prompt, or while the shell's line editor is waiting for input. In the latter case it is useful to be able to produce output that does not interfere with the line being edited. Providing the option -o causes the shell to clear the command line before the event and redraw it afterwards. This should be used with any scheduled event that produces visible output to the terminal; it is not needed, for example, with output that updates a terminal emulator's title bar. To effect changes to the editor buffer when an event executes, use the `zle' command with no arguments to test whether the editor is active, and if it is, then use `zle WIDGET' to access the editor via the named WIDGET. The sched builtin is not made available by default when the shell starts in a mode emulating another shell. It can be made available with the command `zmodload -F zsh/sched b:sched'. zsh_scheduled_events A readonly array corresponding to the events scheduled by the sched builtin. The indices of the array correspond to the numbers shown when sched is run with no arguments (provided that the KSH_ARRAYS option is not set). The value of the array consists of the scheduled time in seconds since the epoch (see *Note The zsh/datetime Module:: for facilities for using this number), followed by a colon, followed by any options (which may be empty but will be preceded by a `-' otherwise), followed by a colon, followed by the command to be executed. The sched builtin should be used for manipulating the events. Note that this will have an immediate effect on the contents of the array, so that indices may become invalid.  File: zsh.info, Node: The zsh/net/socket Module, Next: The zsh/stat Module, Prev: The zsh/sched Module, Up: Zsh Modules 22.25 The zsh/net/socket Module =============================== The zsh/net/socket module makes available one builtin command: zsocket [ -altv ] [ -d FD ] [ ARGS ] zsocket is implemented as a builtin to allow full use of shell command line editing, file I/O, and job control mechanisms. 22.25.1 Outbound Connections ---------------------------- zsocket [ -v ] [ -d FD ] FILENAME Open a new Unix domain connection to FILENAME. The shell parameter REPLY will be set to the file descriptor associated with that connection. Currently, only stream connections are supported. If -d is specified, its argument will be taken as the target file descriptor for the connection. In order to elicit more verbose output, use -v. File descriptors can be closed with normal shell syntax when no longer needed, for example: exec {REPLY}>&- 22.25.2 Inbound Connections --------------------------- zsocket -l [ -v ] [ -d FD ] FILENAME zsocket -l will open a socket listening on FILENAME. The shell parameter REPLY will be set to the file descriptor associated with that listener. The file descriptor remains open in subshells and forked external executables. If -d is specified, its argument will be taken as the target file descriptor for the connection. In order to elicit more verbose output, use -v. zsocket -a [ -tv ] [ -d TARGETFD ] LISTENFD zsocket -a will accept an incoming connection to the socket associated with LISTENFD. The shell parameter REPLY will be set to the file descriptor associated with the inbound connection. The file descriptor remains open in subshells and forked external executables. If -d is specified, its argument will be taken as the target file descriptor for the connection. If -t is specified, zsocket will return if no incoming connection is pending. Otherwise it will wait for one. In order to elicit more verbose output, use -v.  File: zsh.info, Node: The zsh/stat Module, Next: The zsh/system Module, Prev: The zsh/net/socket Module, Up: Zsh Modules 22.26 The zsh/stat Module ========================= The zsh/stat module makes available one builtin command under two possible names: zstat [ -gnNolLtTrs ] [ -f FD ] [ -H HASH ] [ -A ARRAY ] [ -F FMT ] [ +ELEMENT ] [ FILE ... ] stat ... The command acts as a front end to the stat system call (see man page stat(2)). The same command is provided with two names; as the name stat is often used by an external command it is recommended that only the zstat form of the command is used. This can be arranged by loading the module with the command `zmodload -F zsh/stat b:zstat'. If the stat call fails, the appropriate system error message printed and status 1 is returned. The fields of struct stat give information about the files provided as arguments to the command. In addition to those available from the stat call, an extra element `link' is provided. These elements are: device The number of the device on which the file resides. inode The unique number of the file on this device (`_inode_' number). mode The mode of the file; that is, the file's type and access permissions. With the -s option, this will be returned as a string corresponding to the first column in the display of the ls -l command. nlink The number of hard links to the file. uid The user ID of the owner of the file. With the -s option, this is displayed as a user name. gid The group ID of the file. With the -s option, this is displayed as a group name. rdev The raw device number. This is only useful for special devices. size The size of the file in bytes. atime mtime ctime The last access, modification and inode change times of the file, respectively, as the number of seconds since midnight GMT on 1st January, 1970. With the -s option, these are printed as strings for the local time zone; the format can be altered with the -F option, and with the -g option the times are in GMT. blksize The number of bytes in one allocation block on the device on which the file resides. block The number of disk blocks used by the file. link If the file is a link and the -L option is in effect, this contains the name of the file linked to, otherwise it is empty. Note that if this element is selected (``zstat +link'') then the -L option is automatically used. A particular element may be selected by including its name preceded by a `+' in the option list; only one element is allowed. The element may be shortened to any unique set of leading characters. Otherwise, all elements will be shown for all files. Options: -A ARRAY Instead of displaying the results on standard output, assign them to an ARRAY, one struct stat element per array element for each file in order. In this case neither the name of the element nor the name of the files appears in ARRAY unless the -t or -n options were given, respectively. If -t is given, the element name appears as a prefix to the appropriate array element; if -n is given, the file name appears as a separate array element preceding all the others. Other formatting options are respected. -H HASH Similar to -A, but instead assign the values to HASH. The keys are the elements listed above. If the -n option is provided then the name of the file is included in the hash with key name. -f FD Use the file on file descriptor FD instead of named files; no list of file names is allowed in this case. -F FMT Supplies a strftime (see man page strftime(3)) string for the formatting of the time elements. The format string supports all of the zsh extensions described in *Note Prompt Expansion::. The -s option is implied. -g Show the time elements in the GMT time zone. The -s option is implied. -l List the names of the type elements (to standard output or an array as appropriate) and return immediately; arguments, and options other than -A, are ignored. -L Perform an lstat (see man page lstat(2)) rather than a stat system call. In this case, if the file is a link, information about the link itself rather than the target file is returned. This option is required to make the link element useful. It's important to note that this is the exact opposite from man page ls(1), etc. -n Always show the names of files. Usually these are only shown when output is to standard output and there is more than one file in the list. -N Never show the names of files. -o If a raw file mode is printed, show it in octal, which is more useful for human consumption than the default of decimal. A leading zero will be printed in this case. Note that this does not affect whether a raw or formatted file mode is shown, which is controlled by the -r and -s options, nor whether a mode is shown at all. -r Print raw data (the default format) alongside string data (the -s format); the string data appears in parentheses after the raw data. -s Print mode, uid, gid and the three time elements as strings instead of numbers. In each case the format is like that of ls -l. -t Always show the type names for the elements of struct stat. Usually these are only shown when output is to standard output and no individual element has been selected. -T Never show the type names of the struct stat elements.  File: zsh.info, Node: The zsh/system Module, Next: The zsh/net/tcp Module, Prev: The zsh/stat Module, Up: Zsh Modules 22.27 The zsh/system Module =========================== The zsh/system module makes available various builtin commands and parameters. 22.27.1 Builtins ---------------- syserror [ -e ERRVAR ] [ -p PREFIX ] [ ERRNO | ERRNAME ] This command prints out the error message associated with ERRNO, a system error number, followed by a newline to standard error. Instead of the error number, a name ERRNAME, for example ENOENT, may be used. The set of names is the same as the contents of the array errnos, see below. If the string PREFIX is given, it is printed in front of the error message, with no intervening space. If ERRVAR is supplied, the entire message, without a newline, is assigned to the parameter names ERRVAR and nothing is output. A return status of 0 indicates the message was successfully printed (although it may not be useful if the error number was out of the system's range), a return status of 1 indicates an error in the parameters, and a return status of 2 indicates the error name was not recognised (no message is printed for this). sysopen [ -arw ] [ -m PERMISSIONS ] [ -o OPTIONS ] -u FD FILE This command opens a file. The -r, -w and -a flags indicate whether the file should be opened for reading, writing and appending, respectively. The -m option allows the initial permissions to use when creating a file to be specified in octal form. The file descriptor is specified with -u. Either an explicit file descriptor in the range 0 to 9 can be specified or a variable name can be given to which the file descriptor number will be assigned. The -o option allows various system specific options to be specified as a comma-separated list. The following is a list of possible options. Note that, depending on the system, some may not be available. cloexec mark file to be closed when other programs are executed (else the file descriptor remains open in subshells and forked external executables) create creat create file if it does not exist excl create file, error if it already exists noatime suppress updating of the file atime nofollow fail if FILE is a symbolic link sync request that writes wait until data has been physically written truncate trunc truncate file to size 0 To close the file, use one of the following: exec {FD}<&- exec {FD}>&- sysread [ -c COUNTVAR ] [ -i INFD ] [ -o OUTFD ] [ -s BUFSIZE ] [ -t TIMEOUT ] [ PARAM ] Perform a single system read from file descriptor INFD, or zero if that is not given. The result of the read is stored in PARAM or REPLY if that is not given. If COUNTVAR is given, the number of bytes read is assigned to the parameter named by COUNTVAR. The maximum number of bytes read is BUFSIZE or 8192 if that is not given, however the command returns as soon as any number of bytes was successfully read. If TIMEOUT is given, it specifies a timeout in seconds, which may be zero to poll the file descriptor. This is handled by the poll system call if available, otherwise the select system call if available. If OUTFD is given, an attempt is made to write all the bytes just read to the file descriptor OUTFD. If this fails, because of a system error other than EINTR or because of an internal zsh error during an interrupt, the bytes read but not written are stored in the parameter named by PARAM if supplied (no default is used in this case), and the number of bytes read but not written is stored in the parameter named by COUNTVAR if that is supplied. If it was successful, COUNTVAR contains the full number of bytes transferred, as usual, and PARAM is not set. The error EINTR (interrupted system call) is handled internally so that shell interrupts are transparent to the caller. Any other error causes a return. The possible return statuses are 0 At least one byte of data was successfully read and, if appropriate, written. 1 There was an error in the parameters to the command. This is the only error for which a message is printed to standard error. 2 There was an error on the read, or on polling the input file descriptor for a timeout. The parameter ERRNO gives the error. 3 Data were successfully read, but there was an error writing them to OUTFD. The parameter ERRNO gives the error. 4 The attempt to read timed out. Note this does not set ERRNO as this is not a system error. 5 No system error occurred, but zero bytes were read. This usually indicates end of file. The parameters are set according to the usual rules; no write to OUTFD is attempted. sysseek [ -u FD ] [ -w start|end|current ] OFFSET The current file position at which future reads and writes will take place is adjusted to the specified byte offset. The OFFSET is evaluated as a math expression. The -u option allows the file descriptor to be specified. By default the offset is specified relative to the start or the file but, with the -w option, it is possible to specify that the offset should be relative to the current position or the end of the file. syswrite [ -c COUNTVAR ] [ -o OUTFD ] DATA The data (a single string of bytes) are written to the file descriptor OUTFD, or 1 if that is not given, using the write system call. Multiple write operations may be used if the first does not write all the data. If COUNTVAR is given, the number of byte written is stored in the parameter named by COUNTVAR; this may not be the full length of DATA if an error occurred. The error EINTR (interrupted system call) is handled internally by retrying; otherwise an error causes the command to return. For example, if the file descriptor is set to non-blocking output, an error EAGAIN (on some systems, EWOULDBLOCK) may result in the command returning early. The return status may be 0 for success, 1 for an error in the parameters to the command, or 2 for an error on the write; no error message is printed in the last case, but the parameter ERRNO will reflect the error that occurred. zsystem flock [ -t TIMEOUT ] [ -f VAR ] [-er] FILE zsystem flock -u FD_EXPR The builtin zsystem's subcommand flock performs advisory file locking (via the man page fcntl(2) system call) over the entire contents of the given file. This form of locking requires the processes accessing the file to cooperate; its most obvious use is between two instances of the shell itself. In the first form the named FILE, which must already exist, is locked by opening a file descriptor to the file and applying a lock to the file descriptor. The lock terminates when the shell process that created the lock exits; it is therefore often convenient to create file locks within subshells, since the lock is automatically released when the subshell exits. Note that use of the print builtin with the -u option will, as a side effect, release the lock, as will redirection to the file in the shell holding the lock. To work around this use a subshell, e.g. `(print message) >> FILE'. Status 0 is returned if the lock succeeds, else status 1. In the second form the file descriptor given by the arithmetic expression FD_EXPR is closed, releasing a lock. The file descriptor can be queried by using the `-f VAR' form during the lock; on a successful lock, the shell variable VAR is set to the file descriptor used for locking. The lock will be released if the file descriptor is closed by any other means, for example using `exec {VAR}>&-'; however, the form described here performs a safety check that the file descriptor is in use for file locking. By default the shell waits indefinitely for the lock to succeed. The option -t TIMEOUT specifies a timeout for the lock in seconds; currently this must be an integer. The shell will attempt to lock the file once a second during this period. If the attempt times out, status 2 is returned. If the option -e is given, the file descriptor for the lock is preserved when the shell uses exec to start a new process; otherwise it is closed at that point and the lock released. If the option -r is given, the lock is only for reading, otherwise it is for reading and writing. The file descriptor is opened accordingly. zsystem supports SUBCOMMAND The builtin zsystem's subcommand supports tests whether a given subcommand is supported. It returns status 0 if so, else status 1. It operates silently unless there was a syntax error (i.e. the wrong number of arguments), in which case status 255 is returned. Status 1 can indicate one of two things: SUBCOMMAND is known but not supported by the current operating system, or SUBCOMMAND is not known (possibly because this is an older version of the shell before it was implemented). 22.27.2 Math Functions ---------------------- systell(FD) The systell math function returns the current file position for the file descriptor passed as an argument. 22.27.3 Parameters ------------------ errnos A readonly array of the names of errors defined on the system. These are typically macros defined in C by including the system header file errno.h. The index of each name (assuming the option KSH_ARRAYS is unset) corresponds to the error number. Error numbers NUM before the last known error which have no name are given the name ENUM in the array. Note that aliases for errors are not handled; only the canonical name is used. sysparams A readonly associative array. The keys are: pid Returns the process ID of the current process, even in subshells. Compare $$, which returns the process ID of the main shell process. ppid Returns the process ID of the parent of the current process, even in subshells. Compare $PPID, which returns the process ID of the parent of the main shell process. procsubstpid Returns the process ID of the last process started for process substitution, i.e. the <(...) and >(...) expansions.  File: zsh.info, Node: The zsh/net/tcp Module, Next: The zsh/termcap Module, Prev: The zsh/system Module, Up: Zsh Modules 22.28 The zsh/net/tcp Module ============================ The zsh/net/tcp module makes available one builtin command: ztcp [ -acflLtv ] [ -d FD ] [ ARGS ] ztcp is implemented as a builtin to allow full use of shell command line editing, file I/O, and job control mechanisms. If ztcp is run with no options, it will output the contents of its session table. If it is run with only the option -L, it will output the contents of the session table in a format suitable for automatic parsing. The option is ignored if given with a command to open or close a session. The output consists of a set of lines, one per session, each containing the following elements separated by spaces: File descriptor The file descriptor in use for the connection. For normal inbound (I) and outbound (O) connections this may be read and written by the usual shell mechanisms. However, it should only be close with `ztcp -c'. Connection type A letter indicating how the session was created: Z A session created with the zftp command. L A connection opened for listening with `ztcp -l'. I An inbound connection accepted with `ztcp -a'. O An outbound connection created with `ztcp HOST ...'. The local host This is usually set to an all-zero IP address as the address of the localhost is irrelevant. The local port This is likely to be zero unless the connection is for listening. The remote host This is the fully qualified domain name of the peer, if available, else an IP address. It is an all-zero IP address for a session opened for listening. The remote port This is zero for a connection opened for listening. 22.28.1 Outbound Connections ---------------------------- ztcp [ -v ] [ -d FD ] HOST [ PORT ] Open a new TCP connection to HOST. If the PORT is omitted, it will default to port 23. The connection will be added to the session table and the shell parameter REPLY will be set to the file descriptor associated with that connection. If -d is specified, its argument will be taken as the target file descriptor for the connection. In order to elicit more verbose output, use -v. 22.28.2 Inbound Connections --------------------------- ztcp -l [ -v ] [ -d FD ] PORT ztcp -l will open a socket listening on TCP PORT. The socket will be added to the session table and the shell parameter REPLY will be set to the file descriptor associated with that listener. If -d is specified, its argument will be taken as the target file descriptor for the connection. In order to elicit more verbose output, use -v. ztcp -a [ -tv ] [ -d TARGETFD ] LISTENFD ztcp -a will accept an incoming connection to the port associated with LISTENFD. The connection will be added to the session table and the shell parameter REPLY will be set to the file descriptor associated with the inbound connection. If -d is specified, its argument will be taken as the target file descriptor for the connection. If -t is specified, ztcp will return if no incoming connection is pending. Otherwise it will wait for one. In order to elicit more verbose output, use -v. 22.28.3 Closing Connections --------------------------- ztcp -cf [ -v ] [ FD ] ztcp -c [ -v ] [ FD ] ztcp -c will close the socket associated with FD. The socket will be removed from the session table. If FD is not specified, ztcp will close everything in the session table. Normally, sockets registered by zftp (see *Note The zsh/zftp Module:: ) cannot be closed this way. In order to force such a socket closed, use -f. In order to elicit more verbose output, use -v. 22.28.4 Example --------------- Here is how to create a TCP connection between two instances of zsh. We need to pick an unassigned port; here we use the randomly chosen 5123. On host1, zmodload zsh/net/tcp ztcp -l 5123 listenfd=$REPLY ztcp -a $listenfd fd=$REPLY The second from last command blocks until there is an incoming connection. Now create a connection from host2 (which may, of course, be the same machine): zmodload zsh/net/tcp ztcp host1 5123 fd=$REPLY Now on each host, $fd contains a file descriptor for talking to the other. For example, on host1: print This is a message >&$fd and on host2: read -r line <&$fd; print -r - $line prints `This is a message'. To tidy up, on host1: ztcp -c $listenfd ztcp -c $fd and on host2 ztcp -c $fd  File: zsh.info, Node: The zsh/termcap Module, Next: The zsh/terminfo Module, Prev: The zsh/net/tcp Module, Up: Zsh Modules 22.29 The zsh/termcap Module ============================ The zsh/termcap module makes available one builtin command: echotc CAP [ ARG ... ] Output the termcap value corresponding to the capability CAP, with optional arguments. The zsh/termcap module makes available one parameter: termcap An associative array that maps termcap capability codes to their values.  File: zsh.info, Node: The zsh/terminfo Module, Next: The zsh/zftp Module, Prev: The zsh/termcap Module, Up: Zsh Modules 22.30 The zsh/terminfo Module ============================= The zsh/terminfo module makes available one builtin command: echoti CAP [ ARG ] Output the terminfo value corresponding to the capability CAP, instantiated with ARG if applicable. The zsh/terminfo module makes available one parameter: terminfo An associative array that maps terminfo capability names to their values.  File: zsh.info, Node: The zsh/zftp Module, Next: The zsh/zle Module, Prev: The zsh/terminfo Module, Up: Zsh Modules 22.31 The zsh/zftp Module ========================= The zsh/zftp module makes available one builtin command: zftp SUBCOMMAND [ ARGS ] The zsh/zftp module is a client for FTP (file transfer protocol). It is implemented as a builtin to allow full use of shell command line editing, file I/O, and job control mechanisms. Often, users will access it via shell functions providing a more powerful interface; a set is provided with the zsh distribution and is described in *Note Zftp Function System::. However, the zftp command is entirely usable in its own right. All commands consist of the command name zftp followed by the name of a subcommand. These are listed below. The return status of each subcommand is supposed to reflect the success or failure of the remote operation. See a description of the variable ZFTP_VERBOSE for more information on how responses from the server may be printed. 22.31.1 Subcommands ------------------- open HOST[:PORT] [ USER [ PASSWORD [ ACCOUNT ] ] ] Open a new FTP session to HOST, which may be the name of a TCP/IP connected host or an IP number in the standard dot notation. If the argument is in the form HOST:PORT, open a connection to TCP port PORT instead of the standard FTP port 21. This may be the name of a TCP service or a number: see the description of ZFTP_PORT below for more information. If IPv6 addresses in colon format are used, the HOST should be surrounded by quoted square brackets to distinguish it from the PORT, for example '[fe80::203:baff:fe02:8b56]'. For consistency this is allowed with all forms of HOST. Remaining arguments are passed to the login subcommand. Note that if no arguments beyond HOST are supplied, open will _not_ automatically call login. If no arguments at all are supplied, open will use the parameters set by the params subcommand. After a successful open, the shell variables ZFTP_HOST, ZFTP_PORT, ZFTP_IP and ZFTP_SYSTEM are available; see `Variables' below. login [ NAME [ PASSWORD [ ACCOUNT ] ] ] user [ NAME [ PASSWORD [ ACCOUNT ] ] ] Login the user NAME with parameters PASSWORD and ACCOUNT. Any of the parameters can be omitted, and will be read from standard input if needed (NAME is always needed). If standard input is a terminal, a prompt for each one will be printed on standard error and PASSWORD will not be echoed. If any of the parameters are not used, a warning message is printed. After a successful login, the shell variables ZFTP_USER, ZFTP_ACCOUNT and ZFTP_PWD are available; see `Variables' below. This command may be re-issued when a user is already logged in, and the server will first be reinitialized for a new user. params [ HOST [ USER [ PASSWORD [ ACCOUNT ] ] ] ] params - Store the given parameters for a later open command with no arguments. Only those given on the command line will be remembered. If no arguments are given, the parameters currently set are printed, although the password will appear as a line of stars; the return status is one if no parameters were set, zero otherwise. Any of the parameters may be specified as a `?', which may need to be quoted to protect it from shell expansion. In this case, the appropriate parameter will be read from stdin as with the login subcommand, including special handling of PASSWORD. If the `?' is followed by a string, that is used as the prompt for reading the parameter instead of the default message (any necessary punctuation and whitespace should be included at the end of the prompt). The first letter of the parameter (only) may be quoted with a `\'; hence an argument "\\$word" guarantees that the string from the shell parameter $word will be treated literally, whether or not it begins with a `?'. If instead a single `-' is given, the existing parameters, if any, are deleted. In that case, calling open with no arguments will cause an error. The list of parameters is not deleted after a close, however it will be deleted if the zsh/zftp module is unloaded. For example, zftp params ftp.elsewhere.xx juser '?Password for juser: ' will store the host ftp.elsewhere.xx and the user juser and then prompt the user for the corresponding password with the given prompt. test Test the connection; if the server has reported that it has closed the connection (maybe due to a timeout), return status 2; if no connection was open anyway, return status 1; else return status 0. The test subcommand is silent, apart from messages printed by the $ZFTP_VERBOSE mechanism, or error messages if the connection closes. There is no network overhead for this test. The test is only supported on systems with either the select(2) or poll(2) system calls; otherwise the message `not supported on this system' is printed instead. The test subcommand will automatically be called at the start of any other subcommand for the current session when a connection is open. cd DIRECTORY Change the remote directory to DIRECTORY. Also alters the shell variable ZFTP_PWD. cdup Change the remote directory to the one higher in the directory tree. Note that cd .. will also work correctly on non-UNIX systems. dir [ ARG ... ] Give a (verbose) listing of the remote directory. The ARGs are passed directly to the server. The command's behaviour is implementation dependent, but a UNIX server will typically interpret ARGs as arguments to the ls command and with no arguments return the result of `ls -l'. The directory is listed to standard output. ls [ ARG ... ] Give a (short) listing of the remote directory. With no ARG, produces a raw list of the files in the directory, one per line. Otherwise, up to vagaries of the server implementation, behaves similar to dir. type [ TYPE ] Change the type for the transfer to TYPE, or print the current type if TYPE is absent. The allowed values are `A' (ASCII), `I' (Image, i.e. binary), or `B' (a synonym for `I'). The FTP default for a transfer is ASCII. However, if zftp finds that the remote host is a UNIX machine with 8-bit byes, it will automatically switch to using binary for file transfers upon open. This can subsequently be overridden. The transfer type is only passed to the remote host when a data connection is established; this command involves no network overhead. ascii The same as type A. binary The same as type I. mode [ S | B ] Set the mode type to stream (S) or block (B). Stream mode is the default; block mode is not widely supported. remote FILE ... local [ FILE ... ] Print the size and last modification time of the remote or local files. If there is more than one item on the list, the name of the file is printed first. The first number is the file size, the second is the last modification time of the file in the format CCYYMMDDhhmmSS consisting of year, month, date, hour, minutes and seconds in GMT. Note that this format, including the length, is guaranteed, so that time strings can be directly compared via the [[ builtin's < and > operators, even if they are too long to be represented as integers. Not all servers support the commands for retrieving this information. In that case, the remote command will print nothing and return status 2, compared with status 1 for a file not found. The local command (but not remote) may be used with no arguments, in which case the information comes from examining file descriptor zero. This is the same file as seen by a put command with no further redirection. get FILE ... Retrieve all FILEs from the server, concatenating them and sending them to standard output. put FILE ... For each FILE, read a file from standard input and send that to the remote host with the given name. append FILE ... As put, but if the remote FILE already exists, data is appended to it instead of overwriting it. getat FILE POINT putat FILE POINT appendat FILE POINT Versions of get, put and append which will start the transfer at the given POINT in the remote FILE. This is useful for appending to an incomplete local file. However, note that this ability is not universally supported by servers (and is not quite the behaviour specified by the standard). delete FILE ... Delete the list of files on the server. mkdir DIRECTORY Create a new directory DIRECTORY on the server. rmdir DIRECTORY Delete the directory DIRECTORY on the server. rename OLD-NAME NEW-NAME Rename file OLD-NAME to NEW-NAME on the server. site ARG ... Send a host-specific command to the server. You will probably only need this if instructed by the server to use it. quote ARG ... Send the raw FTP command sequence to the server. You should be familiar with the FTP command set as defined in RFC959 before doing this. Useful commands may include STAT and HELP. Note also the mechanism for returning messages as described for the variable ZFTP_VERBOSE below, in particular that all messages from the control connection are sent to standard error. close quit Close the current data connection. This unsets the shell parameters ZFTP_HOST, ZFTP_PORT, ZFTP_IP, ZFTP_SYSTEM, ZFTP_USER, ZFTP_ACCOUNT, ZFTP_PWD, ZFTP_TYPE and ZFTP_MODE. session [ SESSNAME ] Allows multiple FTP sessions to be used at once. The name of the session is an arbitrary string of characters; the default session is called `default'. If this command is called without an argument, it will list all the current sessions; with an argument, it will either switch to the existing session called SESSNAME, or create a new session of that name. Each session remembers the status of the connection, the set of connection-specific shell parameters (the same set as are unset when a connection closes, as given in the description of close), and any user parameters specified with the params subcommand. Changing to a previous session restores those values; changing to a new session initialises them in the same way as if zftp had just been loaded. The name of the current session is given by the parameter ZFTP_SESSION. rmsession [ SESSNAME ] Delete a session; if a name is not given, the current session is deleted. If the current session is deleted, the earliest existing session becomes the new current session, otherwise the current session is not changed. If the session being deleted is the only one, a new session called `default' is created and becomes the current session; note that this is a new session even if the session being deleted is also called `default'. It is recommended that sessions not be deleted while background commands which use zftp are still active. 22.31.2 Parameters ------------------ The following shell parameters are used by zftp. Currently none of them are special. ZFTP_TMOUT Integer. The time in seconds to wait for a network operation to complete before returning an error. If this is not set when the module is loaded, it will be given the default value 60. A value of zero turns off timeouts. If a timeout occurs on the control connection it will be closed. Use a larger value if this occurs too frequently. ZFTP_IP Readonly. The IP address of the current connection in dot notation. ZFTP_HOST Readonly. The hostname of the current remote server. If the host was opened as an IP number, ZFTP_HOST contains that instead; this saves the overhead for a name lookup, as IP numbers are most commonly used when a nameserver is unavailable. ZFTP_PORT Readonly. The number of the remote TCP port to which the connection is open (even if the port was originally specified as a named service). Usually this is the standard FTP port, 21. In the unlikely event that your system does not have the appropriate conversion functions, this appears in network byte order. If your system is little-endian, the port then consists of two swapped bytes and the standard port will be reported as 5376. In that case, numeric ports passed to zftp open will also need to be in this format. ZFTP_SYSTEM Readonly. The system type string returned by the server in response to an FTP SYST request. The most interesting case is a string beginning "UNIX Type: L8", which ensures maximum compatibility with a local UNIX host. ZFTP_TYPE Readonly. The type to be used for data transfers , either `A' or `I'. Use the type subcommand to change this. ZFTP_USER Readonly. The username currently logged in, if any. ZFTP_ACCOUNT Readonly. The account name of the current user, if any. Most servers do not require an account name. ZFTP_PWD Readonly. The current directory on the server. ZFTP_CODE Readonly. The three digit code of the last FTP reply from the server as a string. This can still be read after the connection is closed, and is not changed when the current session changes. ZFTP_REPLY Readonly. The last line of the last reply sent by the server. This can still be read after the connection is closed, and is not changed when the current session changes. ZFTP_SESSION Readonly. The name of the current FTP session; see the description of the session subcommand. ZFTP_PREFS A string of preferences for altering aspects of zftp's behaviour. Each preference is a single character. The following are defined: P Passive: attempt to make the remote server initiate data transfers. This is slightly more efficient than sendport mode. If the letter S occurs later in the string, zftp will use sendport mode if passive mode is not available. S Sendport: initiate transfers by the FTP PORT command. If this occurs before any P in the string, passive mode will never be attempted. D Dumb: use only the bare minimum of FTP commands. This prevents the variables ZFTP_SYSTEM and ZFTP_PWD from being set, and will mean all connections default to ASCII type. It may prevent ZFTP_SIZE from being set during a transfer if the server does not send it anyway (many servers do). If ZFTP_PREFS is not set when zftp is loaded, it will be set to a default of `PS', i.e. use passive mode if available, otherwise fall back to sendport mode. ZFTP_VERBOSE A string of digits between 0 and 5 inclusive, specifying which responses from the server should be printed. All responses go to standard error. If any of the numbers 1 to 5 appear in the string, raw responses from the server with reply codes beginning with that digit will be printed to standard error. The first digit of the three digit reply code is defined by RFC959 to correspond to: 1. A positive preliminary reply. 2. A positive completion reply. 3. A positive intermediate reply. 4. A transient negative completion reply. 5. A permanent negative completion reply. It should be noted that, for unknown reasons, the reply `Service not available', which forces termination of a connection, is classified as 421, i.e. `transient negative', an interesting interpretation of the word `transient'. The code 0 is special: it indicates that all but the last line of multiline replies read from the server will be printed to standard error in a processed format. By convention, servers use this mechanism for sending information for the user to read. The appropriate reply code, if it matches the same response, takes priority. If ZFTP_VERBOSE is not set when zftp is loaded, it will be set to the default value 450, i.e., messages destined for the user and all errors will be printed. A null string is valid and specifies that no messages should be printed. 22.31.3 Functions ----------------- zftp_chpwd If this function is set by the user, it is called every time the directory changes on the server, including when a user is logged in, or when a connection is closed. In the last case, $ZFTP_PWD will be unset; otherwise it will reflect the new directory. zftp_progress If this function is set by the user, it will be called during a get, put or append operation each time sufficient data has been received from the host. During a get, the data is sent to standard output, so it is vital that this function should write to standard error or directly to the terminal, _not_ to standard output. When it is called with a transfer in progress, the following additional shell parameters are set: ZFTP_FILE The name of the remote file being transferred from or to. ZFTP_TRANSFER A G for a get operation and a P for a put operation. ZFTP_SIZE The total size of the complete file being transferred: the same as the first value provided by the remote and local subcommands for a particular file. If the server cannot supply this value for a remote file being retrieved, it will not be set. If input is from a pipe the value may be incorrect and correspond simply to a full pipe buffer. ZFTP_COUNT The amount of data so far transferred; a number between zero and $ZFTP_SIZE, if that is set. This number is always available. The function is initially called with ZFTP_TRANSFER set appropriately and ZFTP_COUNT set to zero. After the transfer is finished, the function will be called one more time with ZFTP_TRANSFER set to GF or PF, in case it wishes to tidy up. It is otherwise never called twice with the same value of ZFTP_COUNT. Sometimes the progress meter may cause disruption. It is up to the user to decide whether the function should be defined and to use unfunction when necessary. 22.31.4 Problems ---------------- A connection may not be opened in the left hand side of a pipe as this occurs in a subshell and the file information is not updated in the main shell. In the case of type or mode changes or closing the connection in a subshell, the information is returned but variables are not updated until the next call to zftp. Other status changes in subshells will not be reflected by changes to the variables (but should be otherwise harmless). Deleting sessions while a zftp command is active in the background can have unexpected effects, even if it does not use the session being deleted. This is because all shell subprocesses share information on the state of all connections, and deleting a session changes the ordering of that information. On some operating systems, the control connection is not valid after a fork(), so that operations in subshells, on the left hand side of a pipeline, or in the background are not possible, as they should be. This is presumably a bug in the operating system.  File: zsh.info, Node: The zsh/zle Module, Next: The zsh/zleparameter Module, Prev: The zsh/zftp Module, Up: Zsh Modules 22.32 The zsh/zle Module ======================== The zsh/zle module contains the Zsh Line Editor. See *Note Zsh Line Editor::.  File: zsh.info, Node: The zsh/zleparameter Module, Next: The zsh/zprof Module, Prev: The zsh/zle Module, Up: Zsh Modules 22.33 The zsh/zleparameter Module ================================= The zsh/zleparameter module defines two special parameters that can be used to access internal information of the Zsh Line Editor (see *Note Zsh Line Editor::). keymaps This array contains the names of the keymaps currently defined. widgets This associative array contains one entry per widget. The name of the widget is the key and the value gives information about the widget. It is either the string `builtin' for builtin widgets, a string of the form `user:NAME' for user-defined widgets, where NAME is the name of the shell function implementing the widget, a string of the form `completion:TYPE:NAME' for completion widgets, or a null value if the widget is not yet fully defined. In the penultimate case, TYPE is the name of the builtin widget the completion widget imitates in its behavior and NAME is the name of the shell function implementing the completion widget.  File: zsh.info, Node: The zsh/zprof Module, Next: The zsh/zpty Module, Prev: The zsh/zleparameter Module, Up: Zsh Modules 22.34 The zsh/zprof Module ========================== When loaded, the zsh/zprof causes shell functions to be profiled. The profiling results can be obtained with the zprof builtin command made available by this module. There is no way to turn profiling off other than unloading the module. zprof [ -c ] Without the -c option, zprof lists profiling results to standard output. The format is comparable to that of commands like gprof. At the top there is a summary listing all functions that were called at least once. This summary is sorted in decreasing order of the amount of time spent in each. The lines contain the number of the function in order, which is used in other parts of the list in suffixes of the form `[NUM]', then the number of calls made to the function. The next three columns list the time in milliseconds spent in the function and its descendants, the average time in milliseconds spent in the function and its descendants per call and the percentage of time spent in all shell functions used in this function and its descendants. The following three columns give the same information, but counting only the time spent in the function itself. The final column shows the name of the function. After the summary, detailed information about every function that was invoked is listed, sorted in decreasing order of the amount of time spent in each function and its descendants. Each of these entries consists of descriptions for the functions that called the function described, the function itself, and the functions that were called from it. The description for the function itself has the same format as in the summary (and shows the same information). The other lines don't show the number of the function at the beginning and have their function named indented to make it easier to distinguish the line showing the function described in the section from the surrounding lines. The information shown in this case is almost the same as in the summary, but only refers to the call hierarchy being displayed. For example, for a calling function the column showing the total running time lists the time spent in the described function and its descendants only for the times when it was called from that particular calling function. Likewise, for a called function, this columns lists the total time spent in the called function and its descendants only for the times when it was called from the function described. Also in this case, the column showing the number of calls to a function also shows a slash and then the total number of invocations made to the called function. As long as the zsh/zprof module is loaded, profiling will be done and multiple invocations of the zprof builtin command will show the times and numbers of calls since the module was loaded. With the -c option, the zprof builtin command will reset its internal counters and will not show the listing.  File: zsh.info, Node: The zsh/zpty Module, Next: The zsh/zselect Module, Prev: The zsh/zprof Module, Up: Zsh Modules 22.35 The zsh/zpty Module ========================= The zsh/zpty module offers one builtin: zpty [ -e ] [ -b ] NAME [ ARG ... ] The arguments following NAME are concatenated with spaces between, then executed as a command, as if passed to the eval builtin. The command runs under a newly assigned pseudo-terminal; this is useful for running commands non-interactively which expect an interactive environment. The NAME is not part of the command, but is used to refer to this command in later calls to zpty. With the -e option, the pseudo-terminal is set up so that input characters are echoed. With the -b option, input to and output from the pseudo-terminal are made non-blocking. The shell parameter REPLY is set to the file descriptor assigned to the master side of the pseudo-terminal. This allows the terminal to be monitored with ZLE descriptor handlers (see *Note Zle Builtins::) or manipulated with sysread and syswrite (see *Note The zsh/system Module::). _Warning_: Use of sysread and syswrite is _not_ recommended; use zpty -r and zpty -w unless you know exactly what you are doing. zpty -d [ NAME ... ] The second form, with the -d option, is used to delete commands previously started, by supplying a list of their NAMEs. If no NAME is given, all commands are deleted. Deleting a command causes the HUP signal to be sent to the corresponding process. zpty -w [ -n ] NAME [ STRING ... ] The -w option can be used to send the to command NAME the given STRINGs as input (separated by spaces). If the -n option is _not_ given, a newline is added at the end. If no STRING is provided, the standard input is copied to the pseudo-terminal; this may stop before copying the full input if the pseudo-terminal is non-blocking. The exact input is always copied: the -n option is not applied. Note that the command under the pseudo-terminal sees this input as if it were typed, so beware when sending special tty driver characters such as word-erase, line-kill, and end-of-file. zpty -r [ -mt ] NAME [ PARAM [ PATTERN ] ] The -r option can be used to read the output of the command NAME. With only a NAME argument, the output read is copied to the standard output. Unless the pseudo-terminal is non-blocking, copying continues until the command under the pseudo-terminal exits; when non-blocking, only as much output as is immediately available is copied. The return status is zero if any output is copied. When also given a PARAM argument, at most one line is read and stored in the parameter named PARAM. Less than a full line may be read if the pseudo-terminal is non-blocking. The return status is zero if at least one character is stored in PARAM. If a PATTERN is given as well, output is read until the whole string read matches the PATTERN, even in the non-blocking case. The return status is zero if the string read matches the pattern, or if the command has exited but at least one character could still be read. If the option -m is present, the return status is zero only if the pattern matches. As of this writing, a maximum of one megabyte of output can be consumed this way; if a full megabyte is read without matching the pattern, the return status is non-zero. In all cases, the return status is non-zero if nothing could be read, and is 2 if this is because the command has finished. If the -r option is combined with the -t option, zpty tests whether output is available before trying to read. If no output is available, zpty immediately returns the status 1. When used with a PATTERN, the behaviour on a failed poll is similar to when the command has exited: the return value is zero if at least one character could still be read even if the pattern failed to match. zpty -t NAME The -t option without the -r option can be used to test whether the command NAME is still running. It returns a zero status if the command is running and a non-zero value otherwise. zpty [ -L ] The last form, without any arguments, is used to list the commands currently defined. If the -L option is given, this is done in the form of calls to the zpty builtin.  File: zsh.info, Node: The zsh/zselect Module, Next: The zsh/zutil Module, Prev: The zsh/zpty Module, Up: Zsh Modules 22.36 The zsh/zselect Module ============================ The zsh/zselect module makes available one builtin command: zselect [ -rwe ] [ -t TIMEOUT ] [ -a ARRAY ] [ -A ASSOC ] [ FD ... ] The zselect builtin is a front-end to the `select' system call, which blocks until a file descriptor is ready for reading or writing, or has an error condition, with an optional timeout. If this is not available on your system, the command prints an error message and returns status 2 (normal errors return status 1). For more information, see your systems documentation for man page select(3). Note there is no connection with the shell builtin of the same name. Arguments and options may be intermingled in any order. Non-option arguments are file descriptors, which must be decimal integers. By default, file descriptors are to be tested for reading, i.e. zselect will return when data is available to be read from the file descriptor, or more precisely, when a read operation from the file descriptor will not block. After a -r, -w and -e, the given file descriptors are to be tested for reading, writing, or error conditions. These options and an arbitrary list of file descriptors may be given in any order. (The presence of an `error condition' is not well defined in the documentation for many implementations of the select system call. According to recent versions of the POSIX specification, it is really an _exception_ condition, of which the only standard example is out-of-band data received on a socket. So zsh users are unlikely to find the -e option useful.) The option `-t TIMEOUT' specifies a timeout in hundredths of a second. This may be zero, in which case the file descriptors will simply be polled and zselect will return immediately. It is possible to call zselect with no file descriptors and a non-zero timeout for use as a finer-grained replacement for `sleep'; note, however, the return status is always 1 for a timeout. The option `-a ARRAY' indicates that ARRAY should be set to indicate the file descriptor(s) which are ready. If the option is not given, the array reply will be used for this purpose. The array will contain a string similar to the arguments for zselect. For example, zselect -t 0 -r 0 -w 1 might return immediately with status 0 and $reply containing `-r 0 -w 1' to show that both file descriptors are ready for the requested operations. The option `-A ASSOC' indicates that the associative array ASSOC should be set to indicate the file descriptor(s) which are ready. This option overrides the option -a, nor will reply be modified. The keys of assoc are the file descriptors, and the corresponding values are any of the characters `rwe' to indicate the condition. The command returns status 0 if some file descriptors are ready for reading. If the operation timed out, or a timeout of 0 was given and no file descriptors were ready, or there was an error, it returns status 1 and the array will not be set (nor modified in any way). If there was an error in the select operation the appropriate error message is printed.  File: zsh.info, Node: The zsh/zutil Module, Prev: The zsh/zselect Module, Up: Zsh Modules 22.37 The zsh/zutil Module ========================== The zsh/zutil module only adds some builtins: zstyle [ -L [ METAPATTERN [ STYLE ] ] ] zstyle [ -e | - | -- ] PATTERN STYLE STRING ... zstyle -d [ PATTERN [ STYLE ... ] ] zstyle -g NAME [ PATTERN [ STYLE ] ] zstyle -{a|b|s} CONTEXT STYLE NAME [ SEP ] zstyle -{T|t} CONTEXT STYLE [ STRING ... ] zstyle -m CONTEXT STYLE PATTERN This builtin command is used to define and lookup styles. Styles are pairs of names and values, where the values consist of any number of strings. They are stored together with patterns and lookup is done by giving a string, called the `_context_', which is matched against the patterns. The definition stored for the most specific pattern that matches will be returned. A pattern is considered to be more specific than another if it contains more components (substrings separated by colons) or if the patterns for the components are more specific, where simple strings are considered to be more specific than patterns and complex patterns are considered to be more specific than the pattern `*'. A `*' in the pattern will match zero or more characters in the context; colons are not treated specially in this regard. If two patterns are equally specific, the tie is broken in favour of the pattern that was defined first. _Example_ For example, to define your preferred form of precipitation depending on which city you're in, you might set the following in your zshrc: zstyle ':weather:europe:*' preferred-precipitation rain zstyle ':weather:europe:germany:* preferred-precipitation none zstyle ':weather:europe:germany:*:munich' preferred-precipitation snow Then, the fictional `weather' plugin might run under the hood a command such as zstyle -s ":weather:${continent}:${country}:${county}:${city}" preferred-precipitation REPLY in order to retrieve your preference into the scalar variable $REPLY. _Usage_ The forms that operate on patterns are the following. zstyle [ -L [ METAPATTERN [ STYLE ] ] ] Without arguments, lists style definitions. Styles are shown in alphabetic order and patterns are shown in the order zstyle will test them. If the -L option is given, listing is done in the form of calls to zstyle. The optional first argument, METAPATTERN, is a pattern which will be matched against the string supplied as PATTERN when the style was defined. Note: this means, for example, `zstyle -L ":completion:*"' will match any supplied pattern beginning `:completion:', not just ":completion:*": use ':completion:\*' to match that. The optional second argument limits the output to a specific STYLE (not a pattern). -L is not compatible with any other options. zstyle [ - | -- | -e ] PATTERN STYLE STRING ... Defines the given STYLE for the PATTERN with the STRINGs as the value. If the -e option is given, the STRINGs will be concatenated (separated by spaces) and the resulting string will be evaluated (in the same way as it is done by the eval builtin command) when the style is looked up. In this case the parameter `reply' must be assigned to set the strings returned after the evaluation. Before evaluating the value, reply is unset, and if it is still unset after the evaluation, the style is treated as if it were not set. zstyle -d [ PATTERN [ STYLE ... ] ] Delete style definitions. Without arguments all definitions are deleted, with a PATTERN all definitions for that pattern are deleted and if any STYLEs are given, then only those styles are deleted for the PATTERN. zstyle -g NAME [ PATTERN [ STYLE ] ] Retrieve a style definition. The NAME is used as the name of an array in which the results are stored. Without any further arguments, all patterns defined are returned. With a PATTERN the styles defined for that pattern are returned and with both a PATTERN and a STYLE, the value strings of that combination is returned. The other forms can be used to look up or test styles for a given context. zstyle -s CONTEXT STYLE NAME [ SEP ] The parameter NAME is set to the value of the style interpreted as a string. If the value contains several strings they are concatenated with spaces (or with the SEP string if that is given) between them. Return 0 if the style is set, 1 otherwise. zstyle -b CONTEXT STYLE NAME The value is stored in NAME as a boolean, i.e. as the string `yes' if the value has only one string and that string is equal to one of `yes', `true', `on', or `1'. If the value is any other string or has more than one string, the parameter is set to `no'. Return 0 if NAME is set to `yes', 1 otherwise. zstyle -a CONTEXT STYLE NAME The value is stored in NAME as an array. If NAME is declared as an associative array, the first, third, etc. strings are used as the keys and the other strings are used as the values. Return 0 if the style is set, 1 otherwise. zstyle -t CONTEXT STYLE [ STRING ... ] zstyle -T CONTEXT STYLE [ STRING ... ] Test the value of a style, i.e. the -t option only returns a status (sets $?). Without any STRING the return status is zero if the style is defined for at least one matching pattern, has only one string in its value, and that is equal to one of `true', `yes', `on' or `1'. If any STRINGs are given the status is zero if and only if at least one of the STRINGs is equal to at least one of the strings in the value. If the style is defined but doesn't match, the return status is 1. If the style is not defined, the status is 2. The -T option tests the values of the style like -t, but it returns status zero (rather than 2) if the style is not defined for any matching pattern. zstyle -m CONTEXT STYLE PATTERN Match a value. Returns status zero if the PATTERN matches at least one of the strings in the value. zformat -f PARAM FORMAT SPEC ... zformat -a ARRAY SEP SPEC ... This builtin provides two different forms of formatting. The first form is selected with the -f option. In this case the FORMAT string will be modified by replacing sequences starting with a percent sign in it with strings from the SPECs. Each SPEC should be of the form `CHAR:STRING' which will cause every appearance of the sequence `%CHAR' in FORMAT to be replaced by the STRING. The `%' sequence may also contain optional minimum and maximum field width specifications between the `%' and the `CHAR' in the form `%MIN.MAXc', i.e. the minimum field width is given first and if the maximum field width is used, it has to be preceded by a dot. Specifying a minimum field width makes the result be padded with spaces to the right if the STRING is shorter than the requested width. Padding to the left can be achieved by giving a negative minimum field width. If a maximum field width is specified, the STRING will be truncated after that many characters. After all `%' sequences for the given SPECs have been processed, the resulting string is stored in the parameter PARAM. The %-escapes also understand ternary expressions in the form used by prompts. The % is followed by a `(' and then an ordinary format specifier character as described above. There may be a set of digits either before or after the `('; these specify a test number, which defaults to zero. Negative numbers are also allowed. An arbitrary delimiter character follows the format specifier, which is followed by a piece of `true' text, the delimiter character again, a piece of `false' text, and a closing parenthesis. The complete expression (without the digits) thus looks like `%(X.TEXT1.TEXT2)', except that the `.' character is arbitrary. The value given for the format specifier in the CHAR:STRING expressions is evaluated as a mathematical expression, and compared with the test number. If they are the same, TEXT1 is output, else TEXT2 is output. A parenthesis may be escaped in TEXT2 as %). Either of TEXT1 or TEXT2 may contain nested %-escapes. For example: zformat -f REPLY "The answer is '%3(c.yes.no)'." c:3 outputs "The answer is 'yes'." to REPLY since the value for the format specifier c is 3, agreeing with the digit argument to the ternary expression. The second form, using the -a option, can be used for aligning strings. Here, the SPECs are of the form `LEFT:RIGHT' where `LEFT' and `RIGHT' are arbitrary strings. These strings are modified by replacing the colons by the SEP string and padding the LEFT strings with spaces to the right so that the SEP strings in the result (and hence the RIGHT strings after them) are all aligned if the strings are printed below each other. All strings without a colon are left unchanged and all strings with an empty RIGHT string have the trailing colon removed. In both cases the lengths of the strings are not used to determine how the other strings are to be aligned. A colon in the LEFT string can be escaped with a backslash. The resulting strings are stored in the ARRAY. zregexparse This implements some internals of the _regex_arguments function. zparseopts [ -D -E -F -K -M ] [ -a ARRAY ] [ -A ASSOC ] [ - ] SPEC ... This builtin simplifies the parsing of options in positional parameters, i.e. the set of arguments given by $*. Each SPEC describes one option and must be of the form `OPT[=ARRAY]'. If an option described by OPT is found in the positional parameters it is copied into the ARRAY specified with the -a option; if the optional `=ARRAY' is given, it is instead copied into that array, which should be declared as a normal array and never as an associative array. Note that it is an error to give any SPEC without an `=ARRAY' unless one of the -a or -A options is used. Unless the -E option is given, parsing stops at the first string that isn't described by one of the SPECs. Even with -E, parsing always stops at a positional parameter equal to `-' or `--'. See also -F. The OPT description must be one of the following. Any of the special characters can appear in the option name provided it is preceded by a backslash. NAME NAME+ The NAME is the name of the option without the leading `-'. To specify a GNU-style long option, one of the usual two leading `-' must be included in NAME; for example, a `--file' option is represented by a NAME of `-file'. If a `+' appears after NAME, the option is appended to ARRAY each time it is found in the positional parameters; without the `+' only the _last_ occurrence of the option is preserved. If one of these forms is used, the option takes no argument, so parsing stops if the next positional parameter does not also begin with `-' (unless the -E option is used). NAME: NAME:- NAME:: If one or two colons are given, the option takes an argument; with one colon, the argument is mandatory and with two colons it is optional. The argument is appended to the ARRAY after the option itself. An optional argument is put into the same array element as the option name (note that this makes empty strings as arguments indistinguishable). A mandatory argument is added as a separate element unless the `:-' form is used, in which case the argument is put into the same element. A `+' as described above may appear between the NAME and the first colon. In all cases, option-arguments must appear either immediately following the option in the same positional parameter or in the next one. Even an optional argument may appear in the next parameter, unless it begins with a `-'. There is no special handling of `=' as with GNU-style argument parsers; given the SPEC `-foo:', the positional parameter `--foo=bar' is parsed as `--foo' with an argument of `=bar'. When the names of two options that take no arguments overlap, the longest one wins, so that parsing for the SPECs `-foo -foobar' (for example) is unambiguous. However, due to the aforementioned handling of option-arguments, ambiguities may arise when at least one overlapping SPEC takes an argument, as in `-foo: -foobar'. In that case, the last matching SPEC wins. The options of zparseopts itself cannot be stacked because, for example, the stack `-DEK' is indistinguishable from a SPEC for the GNU-style long option `--DEK'. The options of zparseopts itself are: -a ARRAY As described above, this names the default array in which to store the recognised options. -A ASSOC If this is given, the options and their values are also put into an associative array with the option names as keys and the arguments (if any) as the values. -D If this option is given, all options found are removed from the positional parameters of the calling shell or shell function, up to but not including any not described by the SPECs. If the first such parameter is `-' or `--', it is removed as well. This is similar to using the shift builtin. -E This changes the parsing rules to _not_ stop at the first string that isn't described by one of the SPECs. It can be used to test for or (if used together with -D) extract options and their arguments, ignoring all other options and arguments that may be in the positional parameters. As indicated above, parsing still stops at the first `-' or `--' not described by a SPEC, but it is not removed when used with -D. -F If this option is given, zparseopts immediately stops at the first option-like parameter not described by one of the SPECs, prints an error message, and returns status 1. Removal (-D) and extraction (-E) are not performed, and option arrays are not updated. This provides basic validation for the given options. Note that the appearance in the positional parameters of an option without its required argument always aborts parsing and returns an error as described above regardless of whether this option is used. -K With this option, the arrays specified with the -a option and with the `=ARRAY' forms are kept unchanged when none of the SPECs for them is used. Otherwise the entire array is replaced when any of the SPECs is used. Individual elements of associative arrays specified with the -A option are preserved by -K. This allows assignment of default values to arrays before calling zparseopts. -M This changes the assignment rules to implement a map among equivalent option names. If any SPEC uses the `=ARRAY' form, the string ARRAY is interpreted as the name of another SPEC, which is used to choose where to store the values. If no other SPEC is found, the values are stored as usual. This changes only the way the values are stored, not the way $* is parsed, so results may be unpredictable if the `NAME+' specifier is used inconsistently. For example, set -- -a -bx -c y -cz baz -cend zparseopts a=foo b:=bar c+:=bar will have the effect of foo=(-a) bar=(-b x -c y -c z) The arguments from `baz' on will not be used. As an example for the -E option, consider: set -- -a x -b y -c z arg1 arg2 zparseopts -E -D b:=bar will have the effect of bar=(-b y) set -- -a x -c z arg1 arg2 I.e., the option -b and its arguments are taken from the positional parameters and put into the array bar. The -M option can be used like this: set -- -a -bx -c y -cz baz -cend zparseopts -A bar -M a=foo b+: c:=b to have the effect of foo=(-a) bar=(-a '' -b xyz)  File: zsh.info, Node: Calendar Function System, Next: TCP Function System, Prev: Zsh Modules, Up: Top 23 Calendar Function System *************************** 23.1 Description ================ The shell is supplied with a series of functions to replace and enhance the traditional Unix calendar programme, which warns the user of imminent or future events, details of which are stored in a text file (typically calendar in the user's home directory). The version provided here includes a mechanism for alerting the user when an event is due. In addition functions age, before and after are provided that can be used in a glob qualifier; they allow files to be selected based on their modification times. The format of the calendar file and the dates used there in and in the age function are described first, then the functions that can be called to examine and modify the calendar file. The functions here depend on the availability of the zsh/datetime module which is usually installed with the shell. The library function strptime() must be available; it is present on most recent operating systems. * Menu: * Calendar File and Date Formats:: * Calendar System User Functions:: * Calendar Styles:: * Calendar Utility Functions:: * Calendar Bugs::  File: zsh.info, Node: Calendar File and Date Formats, Next: Calendar System User Functions, Up: Calendar Function System 23.2 File and Date Formats ========================== 23.2.1 Calendar File Format --------------------------- The calendar file is by default ~/calendar. This can be configured by the calendar-file style, see *Note Calendar Styles::. The basic format consists of a series of separate lines, with no indentation, each including a date and time specification followed by a description of the event. Various enhancements to this format are supported, based on the syntax of Emacs calendar mode. An indented line indicates a continuation line that continues the description of the event from the preceding line (note the date may not be continued in this way). An initial ampersand (&) is ignored for compatibility. An indented line on which the first non-whitespace character is # is not displayed with the calendar entry, but is still scanned for information. This can be used to hide information useful to the calendar system but not to the user, such as the unique identifier used by calendar_add. The Emacs extension that a date with no description may refer to a number of succeeding events at different times is not supported. Unless the done-file style has been altered, any events which have been processed are appended to the file with the same name as the calendar file with the suffix .done, hence ~/calendar.done by default. An example is shown below. 23.2.2 Date Format ------------------ The format of the date and time is designed to allow flexibility without admitting ambiguity. (The words `date' and `time' are both used in the documentation below; except where specifically noted this implies a string that may include both a date and a time specification.) Note that there is no localization support; month and day names must be in English and separator characters are fixed. Matching is case insensitive, and only the first three letters of the names are significant, although as a special case a form beginning "month" does not match "Monday". Furthermore, time zones are not handled; all times are assumed to be local. It is recommended that, rather than exploring the intricacies of the system, users find a date format that is natural to them and stick to it. This will avoid unexpected effects. Various key facts should be noted. * In particular, note the confusion between MONTH/DAY/YEAR and DAY/MONTH/YEAR when the month is numeric; these formats should be avoided if at all possible. Many alternatives are available. * The year must be given in full to avoid confusion, and only years from 1900 to 2099 inclusive are matched. The following give some obvious examples; users finding here a format they like and not subject to vagaries of style may skip the full description. As dates and times are matched separately (even though the time may be embedded in the date), any date format may be mixed with any format for the time of day provide the separators are clear (whitespace, colons, commas). 2007/04/03 13:13 2007/04/03:13:13 2007/04/03 1:13 pm 3rd April 2007, 13:13 April 3rd 2007 1:13 p.m. Apr 3, 2007 13:13 Tue Apr 03 13:13:00 2007 13:13 2007/apr/3 More detailed rules follow. Times are parsed and extracted before dates. They must use colons to separate hours and minutes, though a dot is allowed before seconds if they are present. This limits time formats to the following: * HH:MM[:SS[.FFFFF]] [am|pm|a.m.|p.m.] * HH:MM.SS[.FFFFF] [am|pm|a.m.|p.m.] Here, square brackets indicate optional elements, possibly with alternatives. Fractions of a second are recognised but ignored. For absolute times (the normal format require by the calendar file and the age, before and after functions) a date is mandatory but a time of day is not; the time returned is at the start of the date. One variation is allowed: if a.m. or p.m. or one of their variants is present, an hour without a minute is allowed, e.g. 3 p.m.. Time zones are not handled, though if one is matched following a time specification it will be removed to allow a surrounding date to be parsed. This only happens if the format of the timezone is not too unusual. The following are examples of forms that are understood: +0100 GMT GMT-7 CET+1CDT Any part of the timezone that is not numeric must have exactly three capital letters in the name. Dates suffer from the ambiguity between DD/MM/YYYY and MM/DD/YYYY. It is recommended this form is avoided with purely numeric dates, but use of ordinals, eg. 3rd/04/2007, will resolve the ambiguity as the ordinal is always parsed as the day of the month. Years must be four digits (and the first two must be 19 or 20); 03/04/08 is not recognised. Other numbers may have leading zeroes, but they are not required. The following are handled: * YYYY/MM/DD * YYYY-MM-DD * YYYY/MNM/DD * YYYY-MNM-DD * DD[th|st|rd] MNM[,] [ YYYY ] * MNM DD[th|st|rd][,] [ YYYY ] * DD[th|st|rd]/MM[,] YYYY * DD[th|st|rd]/MM/YYYY * MM/DD[th|st|rd][,] YYYY * MM/DD[th|st|rd]/YYYY Here, MNM is at least the first three letters of a month name, matched case-insensitively. The remainder of the month name may appear but its contents are irrelevant, so janissary, febrile, martial, apricot, maybe, junta, etc. are happily handled. Where the year is shown as optional, the current year is assumed. There are only two such cases, the form Jun 20 or 14 September (the only two commonly occurring forms, apart from a "the" in some forms of English, which isn't currently supported). Such dates will of course become ambiguous in the future, so should ideally be avoided. Times may follow dates with a colon, e.g. 1965/07/12:09:45; this is in order to provide a format with no whitespace. A comma and whitespace are allowed, e.g. 1965/07/12, 09:45. Currently the order of these separators is not checked, so illogical formats such as 1965/07/12, : ,09:45 will also be matched. For simplicity such variations are not shown in the list above. Otherwise, a time is only recognised as being associated with a date if there is only whitespace in between, or if the time was embedded in the date. Days of the week are not normally scanned, but will be ignored if they occur at the start of the date pattern only. However, in contexts where it is useful to specify dates relative to today, days of the week with no other date specification may be given. The day is assumed to be either today or within the past week. Likewise, the words yesterday, today and tomorrow are handled. All matches are case-insensitive. Hence if today is Monday, then Sunday is equivalent to yesterday, Monday is equivalent to today, but Tuesday gives a date six days ago. This is not generally useful within the calendar file. Dates in this format may be combined with a time specification; for example Tomorrow, 8 p.m.. For example, the standard date format: Fri Aug 18 17:00:48 BST 2006 is handled by matching HH:MM:SS and removing it together with the matched (but unused) time zone. This leaves the following: Fri Aug 18 2006 Fri is ignored and the rest is matched according to the standard rules. 23.2.3 Relative Time Format --------------------------- In certain places relative times are handled. Here, a date is not allowed; instead a combination of various supported periods are allowed, together with an optional time. The periods must be in order from most to least significant. In some cases, a more accurate calculation is possible when there is an anchor date: offsets of months or years pick the correct day, rather than being rounded, and it is possible to pick a particular day in a month as `(1st Friday)', etc., as described in more detail below. Anchors are available in the following cases. If one or two times are passed to the function calendar, the start time acts an anchor for the end time when the end time is relative (even if the start time is implicit). When examining calendar files, the scheduled event being examined anchors the warning time when it is given explicitly by means of the WARN keyword; likewise, the scheduled event anchors a repetition period when given by the RPT keyword, so that specifications such as RPT 2 months, 3rd Thursday are handled properly. Finally, the -R argument to calendar_scandate directly provides an anchor for relative calculations. The periods handled, with possible abbreviations are: Years years, yrs, ys, year, yr, y, yearly. A year is 365.25 days unless there is an anchor. Months months, mons, mnths, mths, month, mon, mnth, mth, monthly. Note that m, ms, mn, mns are ambiguous and are _not_ handled. A month is a period of 30 days rather than a calendar month unless there is an anchor. Weeks weeks, wks, ws, week, wk, w, weekly Days days, dys, ds, day, dy, d, daily Hours hours, hrs, hs, hour, hr, h, hourly Minutes minutes, mins, minute, min, but _not_ m, ms, mn or mns Seconds seconds, secs, ss, second, sec, s Spaces between the numbers are optional, but are required between items, although a comma may be used (with or without spaces). The forms yearly to hourly allow the number to be omitted; it is assumed to be 1. For example, 1 d and daily are equivalent. Note that using those forms with plurals is confusing; 2 yearly is the same as 2 years, _not_ twice yearly, so it is recommended they only be used without numbers. When an anchor time is present, there is an extension to handle regular events in the form of the Nth SOMEday of the month. Such a specification must occur immediately after any year and month specification, but before any time of day, and must be in the form N(th|st|rd) DAY, for example 1st Tuesday or 3rd Monday. As in other places, days are matched case insensitively, must be in English, and only the first three letters are significant except that a form beginning `month' does not match `Monday'. No attempt is made to sanitize the resulting date; attempts to squeeze too many occurrences into a month will push the day into the next month (but in the obvious fashion, retaining the correct day of the week). Here are some examples: 30 years 3 months 4 days 3:42:41 14 days 5 hours Monthly, 3rd Thursday 4d,10hr 23.2.4 Example -------------- Here is an example calendar file. It uses a consistent date format, as recommended above. Feb 1, 2006 14:30 Pointless bureaucratic meeting Mar 27, 2006 11:00 Mutual recrimination and finger pointing Bring water pistol and waterproofs Mar 31, 2006 14:00 Very serious managerial pontification # UID 12C7878A9A50 Apr 10, 2006 13:30 Even more pointless blame assignment exercise WARN 30 mins May 18, 2006 16:00 Regular moaning session RPT monthly, 3rd Thursday The second entry has a continuation line. The third entry has a continuation line that will not be shown when the entry is displayed, but the unique identifier will be used by the calendar_add function when updating the event. The fourth entry will produce a warning 30 minutes before the event (to allow you to equip yourself appropriately). The fifth entry repeats after a month on the 3rd Thursday, i.e. June 15, 2006, at the same time.