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


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    <h1 id="firstHeading" class="firstHeading">towlower</h1>            <table class="t-dcl-begin"> <tr class="t-dsc-header"> <th> Defined in header <code>&lt;wctype.h&gt;</code> </th> <th> </th> <th> </th> </tr> <tr class="t-dcl"> <td> <pre data-language="c">wint_t towlower( wint_t wc );</pre>
</td> <td class="t-dcl-nopad"> </td> <td> <span class="t-mark-rev t-since-c95">(since C95)</span> </td> </tr>  </table> <p>Converts the given wide character to lowercase, if possible.</p>
<h3 id="Parameters"> Parameters</h3> <table class="t-par-begin"> <tr class="t-par"> <td> wc </td> <td> - </td> <td> wide character to be converted </td>
</tr>
</table> <h3 id="Return_value"> Return value</h3> <p>Lowercase version of <code>wc</code> or unmodified <code>wc</code> if no lowercase version is listed in the current C locale.</p>
<h3 id="Notes"> Notes</h3> <p>Only 1:1 character mapping can be performed by this function, e.g. the Greek uppercase letter <span class="st0">'Σ'</span> has two lowercase forms, depending on the position in a word: <span class="st0">'σ'</span> and <span class="st0">'ς'</span>. A call to <code>towlower</code> cannot be used to obtain the correct lowercase form in this case.</p>
<p><a rel="nofollow" class="external text" href="http://www.open-std.org/JTC1/SC35/WG5/docs/30112d10.pdf">ISO 30112</a> specifies which pairs of Unicode characters are included in this mapping.</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;
#include &lt;wctype.h&gt;
 
int main(void)
{
    wchar_t wc = L'\u0190'; // Latin capital open E ('Ɛ')
    printf("in the default locale, towlower(%#x) = %#x\n", wc, towlower(wc));
    setlocale(LC_ALL, "en_US.utf8");
    printf("in Unicode locale, towlower(%#x) = %#x\n", wc, towlower(wc));
}</pre></div> <p>Output:</p>
<div class="text source-text"><pre data-language="c">in the default locale, towlower(0x190) = 0x190
in Unicode locale, towlower(0x190) = 0x25b</pre></div> </div> <h3 id="References"> References</h3>  <ul>
<li> C23 standard (ISO/IEC 9899:2023): </li>
<ul><li> 7.30.3.1.1 The towlower function (p: TBD) </li></ul>
<li> C17 standard (ISO/IEC 9899:2018): </li>
<ul><li> 7.30.3.1.1 The towlower function (p: TBD) </li></ul>
<li> C11 standard (ISO/IEC 9899:2011): </li>
<ul><li> 7.30.3.1.1 The towlower function (p: 453) </li></ul>
<li> C99 standard (ISO/IEC 9899:1999): </li>
<ul><li> 7.25.3.1.1 The towlower function (p: 399) </li></ul>
</ul>               <h3 id="See_also"> See also</h3> <table class="t-dsc-begin"> <tr class="t-dsc"> <td> <div><a href="towupper" title="c/string/wide/towupper"> <span class="t-lines"><span>towupper</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> converts a wide character to uppercase <br> <span class="t-mark">(function)</span>  </td>
</tr> <tr class="t-dsc"> <td> <div><a href="../byte/tolower" title="c/string/byte/tolower"> <span class="t-lines"><span>tolower</span></span></a></div> </td> <td> converts a character to lowercase <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/towlower" title="cpp/string/wide/towlower">C++ documentation</a></span> for <code>towlower</code> </td>
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