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  49. <p>
  50. Next: <a href="ispunct.html#ispunct" accesskey="n" rel="next">ispunct</a>, Previous: <a href="islower.html#islower" accesskey="p" rel="prev">islower</a>, Up: <a href="Ctype.html#Ctype" accesskey="u" rel="up">Ctype</a> &nbsp; [<a href="Document-Index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Document-Index.html#Document-Index" title="Index" rel="index">Index</a>]</p>
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  53. <a name="isprint_002c-isgraph_002c-isprint_005fl_002c-isgraph_005fl_002d_002d_002dprintable-character-predicates"></a>
  54. <h3 class="section">3.8 <code>isprint</code>, <code>isgraph</code>, <code>isprint_l</code>, <code>isgraph_l</code>&mdash;printable character predicates</h3>
  55. <a name="index-isprint"></a>
  56. <a name="index-isgraph"></a>
  57. <a name="index-isprint_005fl"></a>
  58. <a name="index-isgraph_005fl"></a>
  59. <p><strong>Synopsis</strong>
  60. </p><div class="example">
  61. <pre class="example">#include &lt;ctype.h&gt;
  62. int isprint(int <var>c</var>);
  63. int isgraph(int <var>c</var>);
  64. #include &lt;ctype.h&gt;
  65. int isprint_l(int <var>c</var>, locale_t <var>locale</var>);
  66. int isgraph_l(int <var>c</var>, locale_t <var>locale</var>);
  67. </pre></div>
  68. <p><strong>Description</strong><br>
  69. <code>isprint</code> is a macro which classifies singlebyte charset values by table
  70. lookup. It is a predicate returning non-zero for printable characters,
  71. and 0 for other character arguments. It is defined only if <var>c</var> is
  72. representable as an unsigned char or if <var>c</var> is EOF.
  73. </p>
  74. <p><code>isgraph</code> behaves identically to <code>isprint</code>, except that space characters
  75. are excluded.
  76. </p>
  77. <p><code>isprint_l</code>, <code>isgraph_l</code> are like <code>isprint</code>, <code>isgraph</code> but perform
  78. the check based on the locale specified by the locale object locale. If
  79. <var>locale</var> is LC_GLOBAL_LOCALE or not a valid locale object, the behaviour
  80. is undefined.
  81. </p>
  82. <p>You can use a compiled subroutine instead of the macro definition by
  83. undefining either macro using &lsquo;<code>#undef isprint</code>&rsquo; or &lsquo;<code>#undef isgraph</code>&rsquo;,
  84. or &lsquo;<code>#undef isprint_l</code>&rsquo; or &lsquo;<code>#undef isgraph_l</code>&rsquo;.
  85. </p>
  86. <br>
  87. <p><strong>Returns</strong><br>
  88. <code>isprint</code>, <code>isprint_l</code> return non-zero if <var>c</var> is a printing character.
  89. <code>isgraph</code>, <code>isgraph_l</code> return non-zero if <var>c</var> is a printing character
  90. except spaces.
  91. </p>
  92. <br>
  93. <p><strong>Portability</strong><br>
  94. <code>isprint</code> and <code>isgraph</code> are ANSI C.
  95. </p>
  96. <p>No supporting OS subroutines are required.
  97. </p>
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