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<h1 id="firstHeading" class="firstHeading">wmemchr</h1> <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code><wchar.h></code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl"> <td> <pre data-language="c">wchar_t *wmemchr( const wchar_t *ptr, wchar_t ch, size_t count );</pre>
</td> <td> (1) </td> <td> <span class="t-mark-rev t-since-c95">(since C95)</span> </td> </tr> <tr class="t-dcl"> <td> <pre data-language="c">/*QWchar_t*/ *wmemchr( /*Qwchar_t*/ *ptr, wchar_t ch, size_t count );</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> Locates the first occurrence of wide character <code>ch</code> in the initial <code>count</code> wide characters of the wide character array or integer array of compatible type, pointed to by <code>ptr</code>.</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 wide character object type. <ul>
<li> If <code>ptr</code> is of type <code>const T*</code>, the return type is <code>const wchar_t*</code>. </li>
<li> Otherwise, if <code>ptr</code> is of type <code>T*</code>, the return type is <code>wchar_t*</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>(wmemchr)</code> or a function pointer is used), the actual function declaration <span class="t-v">(1)</span> becomes visible.</div> <p>If <code>count</code> is zero, the function returns a null pointer.</p>
<h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> ptr </td> <td> - </td> <td> pointer to the wide character array to be examined </td>
</tr> <tr class="t-par"> <td> ch </td> <td> - </td> <td> wide character to search for </td>
</tr> <tr class="t-par"> <td> count </td> <td> - </td> <td> number of wide characters to examine </td>
</tr>
</table> <h3 id="Return_value"> Return value</h3> <p>Pointer to the location of the wide character, or a null pointer if no such character is found.</p>
<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <locale.h>
#include <stdio.h>
#include <wchar.h>
int main(void)
{
wchar_t str[] = L"诺不轻信，故人不负我\0诺不轻许，故我不负人。";
size_t sz = sizeof str / sizeof *str;
wchar_t target = L'许';
wchar_t* result = wmemchr(str, target, sz);
if (result)
{
setlocale(LC_ALL, "en_US.utf8");
printf("Found '%lc' at position %td\n",target, result - str);
}
}</pre></div> <p>Possible output:</p>
<div class="text source-text"><pre data-language="c">Found '许' at position 14</pre></div> </div> <h3 id="References"> References</h3> <ul>
<li> C23 standard (ISO/IEC 9899:2023): </li>
<ul><li> 7.29.4.5.8 The wmemchr function (p: TBD) </li></ul>
<li> C17 standard (ISO/IEC 9899:2018): </li>
<ul><li> 7.29.4.5.8 The wmemchr function (p: TBD) </li></ul>
<li> C11 standard (ISO/IEC 9899:2011): </li>
<ul><li> 7.29.4.5.8 The wmemchr function (p: 438) </li></ul>
<li> C99 standard (ISO/IEC 9899:1999): </li>
<ul><li> 7.24.4.5.8 The wmemchr function (p: 384) </li></ul>
</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="../byte/memchr" title="c/string/byte/memchr"> <span class="t-lines"><span>memchr</span></span></a></div> </td> <td> searches an array for the first occurrence of a character <br> <span class="t-mark">(function)</span> </td>
</tr> <tr class="t-dsc"> <td> <div><a href="wcschr" title="c/string/wide/wcschr"> <span class="t-lines"><span>wcschr</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> finds the first occurrence of a wide character in a wide string <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/wmemchr" title="cpp/string/wide/wmemchr">C++ documentation</a></span> for <code>wmemchr</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/wide/wmemchr" class="_attribution-link">https://en.cppreference.com/w/c/string/wide/wmemchr</a>
</p>
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