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diff --git a/devdocs/c/string%2Fbyte%2Fstrstr.html b/devdocs/c/string%2Fbyte%2Fstrstr.html new file mode 100644 index 00000000..0d03ea16 --- /dev/null +++ b/devdocs/c/string%2Fbyte%2Fstrstr.html @@ -0,0 +1,56 @@ + <h1 id="firstHeading" class="firstHeading">strstr</h1> <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code><string.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl"> <td> <pre data-language="c">char *strstr( const char *str, const char *substr );</pre> +</td> <td> (1) </td> <td class="t-dcl-nopad"> </td> </tr> <tr class="t-dcl t-since-c23"> <td> <pre data-language="c">/*QChar*/ *strstr( /*QChar*/ *str, const char *substr );</pre> +</td> <td> (2) </td> <td> <span class="t-mark-rev t-since-c23">(since C23)</span> </td> </tr> </table> <div class="t-li1"> +<span class="t-li">1)</span> Finds the first occurrence of the null-terminated byte string pointed to by <code>substr</code> in the null-terminated byte string pointed to by <code>str</code>. The terminating null characters are not compared.</div> <div class="t-li1"> +<span class="t-li">2)</span> Type-generic function equivalent to <span class="t-v">(1)</span>. Let <code>T</code> be an unqualified character object type. <ul> +<li> If <code>str</code> is of type <code>const T*</code>, the return type is <code>const char*</code>. </li> +<li> Otherwise, if <code>str</code> is of type <code>T*</code>, the return type is <code>char*</code>. </li> +<li> Otherwise, the behavior is undefined. </li> +</ul> If a macro definition of each of these generic functions is suppressed to access an actual function (e.g. if <code>(strstr)</code> or a function pointer is used), the actual function declaration <span class="t-v">(1)</span> becomes visible.</div> <p>The behavior is undefined if either <code>str</code> or <code>substr</code> is not a pointer to a null-terminated byte string.</p> +<h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> str </td> <td> - </td> <td> pointer to the null-terminated byte string to examine </td> +</tr> <tr class="t-par"> <td> substr </td> <td> - </td> <td> pointer to the null-terminated byte string to search for </td> +</tr> +</table> <h3 id="Return_value"> Return value</h3> <p>Pointer to the first character of the found substring in <code>str</code>, or a null pointer if such substring is not found. If <code>substr</code> points to an empty string, <code>str</code> is returned.</p> +<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <string.h> +#include <stdio.h> + +void find_str(char const *str, char const *substr) +{ + char *pos = strstr(str, substr); + pos ? printf("found the string '%s' in '%s' at position %td\n", + substr, str, pos - str) + : printf("the string '%s' was not found in '%s'\n", + substr, str); +} + +int main(void) +{ + char *str = "one two three"; + find_str(str, "two"); + find_str(str, ""); + find_str(str, "nine"); + find_str(str, "n"); + + return 0; +}</pre></div> <p>Output:</p> +<div class="text source-text"><pre data-language="c">found the string 'two' in 'one two three' at position 4 +found the string '' in 'one two three' at position 0 +the string 'nine' was not found in 'one two three' +found the string 'n' in 'one two three' at position 1</pre></div> </div> <h3 id="References"> References</h3> <ul> +<li> C17 standard (ISO/IEC 9899:2018): </li> +<ul><li> 7.24.5.7 The strstr function (p: 269) </li></ul> +<li> C11 standard (ISO/IEC 9899:2011): </li> +<ul><li> 7.24.5.7 The strstr function (p: 369) </li></ul> +<li> C99 standard (ISO/IEC 9899:1999): </li> +<ul><li> 7.21.5.7 The strstr function (p: 332) </li></ul> +<li> C89/C90 standard (ISO/IEC 9899:1990): </li> +<ul><li> 4.11.5.7 The strstr function </li></ul> +</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="strchr" title="c/string/byte/strchr"> <span class="t-lines"><span>strchr</span></span></a></div> </td> <td> finds the first occurrence of a character <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td> <div><a href="strrchr" title="c/string/byte/strrchr"> <span class="t-lines"><span>strrchr</span></span></a></div> </td> <td> finds the last occurrence of a character <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td colspan="2"> <span><a href="https://en.cppreference.com/w/cpp/string/byte/strstr" title="cpp/string/byte/strstr">C++ documentation</a></span> for <code>strstr</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/string/byte/strstr" class="_attribution-link">https://en.cppreference.com/w/c/string/byte/strstr</a> + </p> +</div> |