devdocs/c/string%2Fwide%2Fwcscmp.html


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    <h1 id="firstHeading" class="firstHeading">wcscmp</h1>            <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code>&lt;wchar.h&gt;</code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl"> <td> <pre data-language="c">int wcscmp( const wchar_t* lhs, const wchar_t* rhs );</pre>
</td> <td class="t-dcl-nopad"> </td> <td> <span class="t-mark-rev t-since-c95">(since C95)</span> </td> </tr>  </table> <p>Compares two null-terminated wide strings lexicographically.</p>
<p>The sign of the result is the sign of the difference between the values of the first pair of wide characters that differ in the strings being compared.</p>
<p>The behavior is undefined if <code>lhs</code> or <code>rhs</code> are not pointers to null-terminated wide strings.</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 null-terminated wide strings 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.</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="wcscoll" title="c/string/wide/wcscoll">wcscoll</a></code>, and the order may not be meaningful when characters from different Unicode blocks are used together or when the order of code units does not match any collation order.</p>
<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include &lt;locale.h&gt;
#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
 
void demo(const wchar_t* lhs, const wchar_t* rhs)
{
    int rc = wcscmp(lhs, rhs);
    const char *rel = rc &lt; 0 ? "precedes" : rc &gt; 0 ? "follows" : "equals";
 
    setlocale(LC_ALL, "en_US.utf8");
    printf("[%ls] %s [%ls]\n", lhs, rel, rhs);
}
 
int main(void)
{
    const wchar_t* string = L"どうもありがとうございます";
    demo(string, L"どうも");
    demo(string, L"助かった");
    demo(string + 9, L"ありがとうございます" + 6);
}</pre></div> <p>Possible output:</p>
<div class="text source-text"><pre data-language="c">[どうもありがとうございます] follows [どうも]
[どうもありがとうございます] precedes [助かった]
[ざいます] equals [ざいます]</pre></div> </div> <h3 id="References"> References</h3>  <ul>
<li> C23 standard (ISO/IEC 9899:2023): </li>
<ul><li> 7.29.4.4.1 The wcscmp function (p: TBD) </li></ul>
<li> C17 standard (ISO/IEC 9899:2018): </li>
<ul><li> 7.29.4.4.1 The wcscmp function (p: TBD) </li></ul>
<li> C11 standard (ISO/IEC 9899:2011): </li>
<ul><li> 7.29.4.4.1 The wcscmp function (p: 433) </li></ul>
<li> C99 standard (ISO/IEC 9899:1999): </li>
<ul><li> 7.24.4.4.1 The wcscmp function (p: 379) </li></ul>
</ul>               <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="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="wmemcmp" title="c/string/wide/wmemcmp"> <span class="t-lines"><span>wmemcmp</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 wide characters from two arrays <br> <span class="t-mark">(function)</span>  </td>
</tr> <tr class="t-dsc"> <td> <div><a href="../byte/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="wcscoll" title="c/string/wide/wcscoll"> <span class="t-lines"><span>wcscoll</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 two wide 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/wide/wcscmp" title="cpp/string/wide/wcscmp">C++ documentation</a></span> for <code>wcscmp</code> </td>
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