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diff --git a/devdocs/c/string%2Fbyte%2Fstrncmp.html b/devdocs/c/string%2Fbyte%2Fstrncmp.html new file mode 100644 index 00000000..d2dc2071 --- /dev/null +++ b/devdocs/c/string%2Fbyte%2Fstrncmp.html @@ -0,0 +1,58 @@ + <h1 id="firstHeading" class="firstHeading">strncmp</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 class="t-dcl-nopad"> <pre data-language="c">int strncmp( const char* lhs, const char* rhs, size_t count );</pre> +</td> <td class="t-dcl-nopad"> </td> <td class="t-dcl-nopad"> </td> </tr> </table> <p>Compares at most <code>count</code> characters of two possibly null-terminated arrays. The comparison is done lexicographically. Characters following the null character are not compared.</p> +<p>The sign of the result is the sign of the difference between the values of the first pair of characters (both interpreted as <code>unsigned char</code>) that differ in the arrays being compared.</p> +<p>The behavior is undefined when access occurs past the end of either array <code>lhs</code> or <code>rhs</code>. The behavior is undefined when either <code>lhs</code> or <code>rhs</code> is the null pointer.</p> +<h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> lhs, rhs </td> <td> - </td> <td> pointers to the possibly null-terminated arrays to compare </td> +</tr> <tr class="t-par"> <td> count </td> <td> - </td> <td> maximum number of characters to compare </td> +</tr> +</table> <h3 id="Return_value"> Return value</h3> <p>Negative value if <code>lhs</code> appears before <code>rhs</code> in lexicographical order.</p> +<p>Zero if <code>lhs</code> and <code>rhs</code> compare equal, or if count is zero.</p> +<p>Positive value if <code>lhs</code> appears after <code>rhs</code> in lexicographical order.</p> +<h3 id="Notes"> Notes</h3> <p>This function is not locale-sensitive, unlike <code><a href="strcoll" title="c/string/byte/strcoll">strcoll</a></code> and <code><a href="strxfrm" title="c/string/byte/strxfrm">strxfrm</a></code>.</p> +<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <stdio.h> +#include <string.h> + +void demo(const char* lhs, const char* rhs, int sz) +{ + const int rc = strncmp(lhs, rhs, sz); + if (rc < 0) + printf("First %d chars of [%s] precede [%s]\n", sz, lhs, rhs); + else if (rc > 0) + printf("First %d chars of [%s] follow [%s]\n", sz, lhs, rhs); + else + printf("First %d chars of [%s] equal [%s]\n", sz, lhs, rhs); +} +int main(void) +{ + const char* string = "Hello World!"; + demo(string, "Hello!", 5); + demo(string, "Hello", 10); + demo(string, "Hello there", 10); + demo("Hello, everybody!" + 12, "Hello, somebody!" + 11, 5); +}</pre></div> <p>Output:</p> +<div class="text source-text"><pre data-language="c">First 5 chars of [Hello World!] equal [Hello!] +First 10 chars of [Hello World!] follow [Hello] +First 10 chars of [Hello World!] precede [Hello there] +First 5 chars of [body!] equal [body!]</pre></div> </div> <h3 id="References"> References</h3> <ul> +<li> C23 standard (ISO/IEC 9899:2023): </li> +<ul><li> 7.24.4.4 The strncmp function (p: TBD) </li></ul> +<li> C17 standard (ISO/IEC 9899:2018): </li> +<ul><li> 7.24.4.4 The strncmp function (p: TBD) </li></ul> +<li> C11 standard (ISO/IEC 9899:2011): </li> +<ul><li> 7.24.4.4 The strncmp function (p: 366) </li></ul> +<li> C99 standard (ISO/IEC 9899:1999): </li> +<ul><li> 7.21.4.4 The strncmp function (p: 329) </li></ul> +<li> C89/C90 standard (ISO/IEC 9899:1990): </li> +<ul><li> 4.11.4.4 The strncmp function </li></ul> +</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="strcmp" title="c/string/byte/strcmp"> <span class="t-lines"><span>strcmp</span></span></a></div> </td> <td> compares two strings <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td> <div><a href="../wide/wcsncmp" title="c/string/wide/wcsncmp"> <span class="t-lines"><span>wcsncmp</span></span></a></div> +<div><span class="t-lines"><span><span class="t-mark-rev t-since-c95">(C95)</span></span></span></div> </td> <td> compares a certain amount of characters from two wide strings <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td> <div><a href="memcmp" title="c/string/byte/memcmp"> <span class="t-lines"><span>memcmp</span></span></a></div> </td> <td> compares two buffers <br> <span class="t-mark">(function)</span> </td> +</tr> <tr class="t-dsc"> <td> <div><a href="strcoll" title="c/string/byte/strcoll"> <span class="t-lines"><span>strcoll</span></span></a></div> </td> <td> compares two strings in accordance to the current locale <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/strncmp" title="cpp/string/byte/strncmp">C++ documentation</a></span> for <code>strncmp</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/strncmp" class="_attribution-link">https://en.cppreference.com/w/c/string/byte/strncmp</a> + </p> +</div> |