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  53. <a name="wcstombs_002d_002d_002dminimal-wide-char-string-to-multibyte-string-converter"></a>
  54. <h3 class="section">2.50 <code>wcstombs</code>&mdash;minimal wide char string to multibyte string converter</h3>
  55. <a name="index-wcstombs"></a>
  56. <p><strong>Synopsis</strong>
  57. </p><div class="example">
  58. <pre class="example">#include &lt;stdlib.h&gt;
  59. size_t wcstombs(char *restrict <var>s</var>, const wchar_t *restrict <var>pwc</var>, size_t <var>n</var>);
  60. </pre></div>
  61. <p><strong>Description</strong><br>
  62. When _MB_CAPABLE is not defined, this is a minimal ANSI-conforming
  63. implementation of <code>wcstombs</code>. In this case,
  64. all wide-characters are expected to represent single bytes and so
  65. are converted simply by casting to char.
  66. </p>
  67. <p>When _MB_CAPABLE is defined, this routine calls <code>_wcstombs_r</code> to perform
  68. the conversion, passing a state variable to allow state dependent
  69. decoding. The result is based on the locale setting which may
  70. be restricted to a defined set of locales.
  71. </p>
  72. <br>
  73. <p><strong>Returns</strong><br>
  74. This implementation of <code>wcstombs</code> returns <code>0</code> if
  75. <var>s</var> is <code>NULL</code> or is the empty string;
  76. it returns <code>-1</code> if _MB_CAPABLE and one of the
  77. wide-char characters does not represent a valid multi-byte character;
  78. otherwise it returns the minimum of: <code>n</code> or the
  79. number of bytes that are transferred to <code>s</code>, not including the
  80. nul terminator.
  81. </p>
  82. <p>If the return value is -1, the state of the <code>pwc</code> string is
  83. indeterminate. If the input has a length of 0, the output
  84. string will be modified to contain a wchar_t nul terminator if
  85. <code>n</code> &gt; 0.
  86. </p>
  87. <br>
  88. <p><strong>Portability</strong><br>
  89. <code>wcstombs</code> is required in the ANSI C standard. However, the precise
  90. effects vary with the locale.
  91. </p>
  92. <p><code>wcstombs</code> requires no supporting OS subroutines.
  93. </p>
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