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| author | Craig Jennings <c@cjennings.net> | 2025-08-14 22:58:58 -0500 |
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| committer | Craig Jennings <c@cjennings.net> | 2025-08-14 22:58:58 -0500 |
| commit | 82ba818ff456bcd6d56a06226e3f27e98fbb55c3 (patch) | |
| tree | 158cfc17b2f644a10f063cb546752cfaae12c97f /devdocs/c/string%2Fwide%2Fwcsncpy.html | |
| parent | 9278ddd4ea1a8b1a4c1edaa8894516e3f48d245b (diff) | |
| download | dotemacs-82ba818ff456bcd6d56a06226e3f27e98fbb55c3.tar.gz dotemacs-82ba818ff456bcd6d56a06226e3f27e98fbb55c3.zip | |
removing all downloaded devdocs files
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diff --git a/devdocs/c/string%2Fwide%2Fwcsncpy.html b/devdocs/c/string%2Fwide%2Fwcsncpy.html deleted file mode 100644 index 7cc3efa4..00000000 --- a/devdocs/c/string%2Fwide%2Fwcsncpy.html +++ /dev/null @@ -1,76 +0,0 @@ - <h1 id="firstHeading" class="firstHeading">wcsncpy, wcsncpy_s</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-rev-aux"> <td></td> <td rowspan="3">(1)</td> <td></td> </tr> <tr class="t-dcl t-since-c95 t-until-c99"> <td> <pre data-language="c">wchar_t* wcsncpy( wchar_t* dest, const wchar_t* src, size_t count );</pre> -</td> <td> <span class="t-mark-rev t-since-c95">(since C95)</span> <br><span class="t-mark-rev t-until-c99">(until C99)</span> </td> </tr> <tr class="t-dcl t-since-c99"> <td> <pre data-language="c">wchar_t *wcsncpy( wchar_t *restrict dest, const wchar_t *restrict src, size_t count );</pre> -</td> <td> <span class="t-mark-rev t-since-c99">(since C99)</span> </td> </tr> <tr class="t-dcl t-since-c11"> <td> <pre data-language="c">errno_t wcsncpy_s( wchar_t *restrict dest, rsize_t destsz, - const wchar_t *restrict src, rsize_t count);</pre> -</td> <td> (2) </td> <td> <span class="t-mark-rev t-since-c11">(since C11)</span> </td> </tr> </table> <div class="t-li1"> -<span class="t-li">1)</span> Copies at most <code>count</code> characters of the wide string pointed to by <code>src</code> (including the terminating null wide character) to wide character array pointed to by <code>dest</code>. </div> <div class="t-li1"> - If <code>count</code> is reached before the entire string <code>src</code> was copied, the resulting wide character array is not null-terminated.</div> <div class="t-li1"> - If, after copying the terminating null wide character from <code>src</code>, <code>count</code> is not reached, additional null wide characters are written to <code>dest</code> until the total of <code>count</code> characters have been written.</div> <div class="t-li1"> - If the strings overlap, the behavior is undefined.</div> <div class="t-li1"> -<span class="t-li">2)</span> Same as <span class="t-v">(1)</span>, except that the function does not continue writing zeroes into the destination array to pad up to <code>count</code>, it stops after writing the terminating null character (if there was no null in the source, it writes one at <code>dest[count]</code> and then stops). Also, the following errors are detected at runtime and call the currently installed <a href="../../error/set_constraint_handler_s" title="c/error/set constraint handler s">constraint handler</a> function: <dl> -<dd> -<ul> -<li> <code>src</code> or <code>dest</code> is a null pointer </li> -<li> <code>destsz</code> or <code>count</code> is zero or greater than <code>RSIZE_MAX/sizeof(wchar_t)</code> </li> -<li> <code>count</code> is greater or equal <code>destsz</code>, but <code>destsz</code> is less or equal <code>wcsnlen_s(src, count)</code>, in other words, truncation would occur </li> -<li> overlap would occur between the source and the destination strings </li> -</ul> </dd> -<dd>As with all bounds-checked functions, <code>wcsncpy_s</code> only guaranteed to be available if <code>__STDC_LIB_EXT1__</code> is defined by the implementation and if the user defines <code>__STDC_WANT_LIB_EXT1__</code> to the integer constant <code>1</code> before including <a href="../wide" title="c/string/wide"><code><wchar.h></code></a>.</dd> -</dl> -</div> <h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> dest </td> <td> - </td> <td> pointer to the wide character array to copy to </td> -</tr> <tr class="t-par"> <td> src </td> <td> - </td> <td> pointer to the wide string to copy from </td> -</tr> <tr class="t-par"> <td> count </td> <td> - </td> <td> maximum number of wide characters to copy </td> -</tr> <tr class="t-par"> <td> destsz </td> <td> - </td> <td> the size of the destination buffer </td> -</tr> -</table> <h3 id="Return_value"> Return value</h3> <div class="t-li1"> -<span class="t-li">1)</span> returns a copy of <code>dest</code> -</div> <div class="t-li1"> -<span class="t-li">2)</span> returns zero on success, returns non-zero on error. Also, on error, writes <code>L'\0'</code> to <code>dest[0]</code> (unless <code>dest</code> is a null pointer or <code>destsz</code> is zero or greater than <code>RSIZE_MAX/sizeof(wchar_t)</code>) and may clobber the rest of the destination array with unspecified values.</div> <h3 id="Notes"> Notes</h3> <p>In typical usage, <code>count</code> is the number of elements in the destination array.</p> -<p>Although truncation to fit the destination buffer is a security risk and therefore a runtime constraints violation for <code>wcsncpy_s</code>, it is possible to get the truncating behavior by specifying <code>count</code> equal to the size of the destination array minus one: it will copy the first <code>count</code> wide characters and append the null wide terminator as always: <code>wcsncpy_s(dst, sizeof dst / sizeof *dst, src, (sizeof dst / sizeof *dst)-1);</code></p> -<h3 id="Example"> Example</h3> <div class="t-example"> <div class="c source-c"><pre data-language="c">#include <stdio.h> -#include <wchar.h> -#include <locale.h> - -int main(void) -{ - const wchar_t src[] = L"わゐ"; - wchar_t dest[6] = {L'あ', L'い', L'う', L'え', L'お'}; - - wcsncpy(dest, src, 4); // this will copy わゐ and repeat L'\0' two times - - puts("The contents of dest are: "); - setlocale(LC_ALL, "en_US.utf8"); - - const long dest_size = sizeof dest / sizeof *dest; - for(wchar_t* p = dest; p-dest != dest_size; ++p) { - *p ? printf("%lc ", *p) - : printf("\\0 "); - } -}</pre></div> <p>Possible output:</p> -<div class="text source-text"><pre data-language="c">The contents of dest are: -わ ゐ \0 \0 お \0</pre></div> </div> <h3 id="References"> References</h3> <ul> -<li> C17 standard (ISO/IEC 9899:2018): </li> -<ul> -<li> 7.29.4.2.2 The wcsncpy function (p: 314) </li> -<li> K.3.9.2.1.2 The wcsncpy_s function (p: 464) </li> -</ul> -<li> C11 standard (ISO/IEC 9899:2011): </li> -<ul> -<li> 7.29.4.2.2 The wcsncpy function (p: 431) </li> -<li> K.3.9.2.1.2 The wcsncpy_s function (p: 640-641) </li> -</ul> -<li> C99 standard (ISO/IEC 9899:1999): </li> -<ul><li> 7.24.4.2.2 The wcsncpy function (p: 377) </li></ul> -</ul> <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="wcscpy" title="c/string/wide/wcscpy"> <span class="t-lines"><span>wcscpy</span><span>wcscpy_s</span></span></a></div> -<div><span class="t-lines"><span><span class="t-mark-rev t-since-c95">(C95)</span></span><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div> </td> <td> copies one wide string to another <br> <span class="t-mark">(function)</span> </td> -</tr> <tr class="t-dsc"> <td> <div><a href="wmemcpy" title="c/string/wide/wmemcpy"> <span class="t-lines"><span>wmemcpy</span><span>wmemcpy_s</span></span></a></div> -<div><span class="t-lines"><span><span class="t-mark-rev t-since-c95">(C95)</span></span><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div> </td> <td> copies a certain amount of wide characters between two non-overlapping arrays <br> <span class="t-mark">(function)</span> </td> -</tr> <tr class="t-dsc"> <td> <div><a href="../byte/strncpy" title="c/string/byte/strncpy"> <span class="t-lines"><span>strncpy</span><span>strncpy_s</span></span></a></div> -<div><span class="t-lines"><span><span class="t-mark-rev t-since-c11">(C11)</span></span></span></div> </td> <td> copies a certain amount of characters from one string to another <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/wcsncpy" title="cpp/string/wide/wcsncpy">C++ documentation</a></span> for <code>wcsncpy</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/wcsncpy" class="_attribution-link">https://en.cppreference.com/w/c/string/wide/wcsncpy</a> - </p> -</div> |
