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diff --git a/devdocs/c/program%2Fsig_strategies.html b/devdocs/c/program%2Fsig_strategies.html new file mode 100644 index 00000000..f4a8f245 --- /dev/null +++ b/devdocs/c/program%2Fsig_strategies.html @@ -0,0 +1,41 @@ + <h1 id="firstHeading" class="firstHeading">SIG_DFL, SIG_IGN</h1> <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code><signal.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl"> <td class="t-dcl-nopad"> <pre data-language="c">#define SIG_DFL /*implementation defined*/</pre> +</td> <td class="t-dcl-nopad"> </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl"> <td class="t-dcl-nopad"> <pre data-language="c">#define SIG_IGN /*implementation defined*/</pre> +</td> <td class="t-dcl-nopad"> </td> <td class="t-dcl-nopad"> </td> </tr> </table> <p>The <code>SIG_DFL</code> and <code>SIG_IGN</code> macros expand into integral expressions that are not equal to an address of any function. The macros define signal handling strategies for <code><a href="http://en.cppreference.com/w/c/program/signal"><span class="kw497">signal</span></a><span class="br0">(</span><span class="br0">)</span></code> function.</p> +<table class="t-dsc-begin"> <tr class="t-dsc-hitem"> <th> Constant </th> <th> Explanation </th> +</tr> <tr class="t-dsc"> <td> <code>SIG_DFL</code> </td> <td> default signal handling </td> +</tr> <tr class="t-dsc"> <td> <code>SIG_IGN</code> </td> <td> signal is ignored </td> +</tr> </table> <h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <signal.h> +#include <stdio.h> + +int main(void) +{ + /* using the default signal handler */ + raise(SIGTERM); + printf("Exit main()\n"); /* never reached */ +}</pre></div> <p>Output:</p> +<div class="text source-text"><pre data-language="c">(none)</pre></div> </div> <h3 id="Example_2"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <signal.h> +#include <stdio.h> + +int main(void) +{ + /* ignoring the signal */ + signal(SIGTERM, SIG_IGN); + raise(SIGTERM); + printf("Exit main()\n"); +}</pre></div> <p>Output:</p> +<div class="text source-text"><pre data-language="c">Exit main()</pre></div> </div> <h3 id="References"> References</h3> <ul> +<li> C17 standard (ISO/IEC 9899:2018): </li> +<ul><li> 7.14/3 Signal handling <signal.h> (p: 193) </li></ul> +<li> C11 standard (ISO/IEC 9899:2011): </li> +<ul><li> 7.14/3 Signal handling <signal.h> (p: 265) </li></ul> +<li> C99 standard (ISO/IEC 9899:1999): </li> +<ul><li> 7.14/3 Signal handling <signal.h> (p: 246) </li></ul> +<li> C89/C90 standard (ISO/IEC 9899:1990): </li> +<ul><li> 4.7 SIGNAL HANDLING <signal.h> </li></ul> +</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/utility/program/SIG_strategies" title="cpp/utility/program/SIG strategies">C++ documentation</a></span> for <code>SIG_DFL, SIG_IGN</code> </td> +</tr> </table> <div class="_attribution"> + <p class="_attribution-p"> + © cppreference.com<br>Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.<br> + <a href="https://en.cppreference.com/w/c/program/SIG_strategies" class="_attribution-link">https://en.cppreference.com/w/c/program/SIG_strategies</a> + </p> +</div> |