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<a name="getchar_002d_002d_002dread-a-character-_0028macro_0029"></a>
<h3 class="section">4.35 <code>getchar</code>&mdash;read a character (macro)</h3>
<a name="index-getchar"></a>
<a name="index-_005fgetchar_005fr"></a>
<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include &lt;stdio.h&gt;
int getchar(void);

int _getchar_r(struct _reent *<var>reent</var>);

</pre></div>
<p><strong>Description</strong><br>
<code>getchar</code> is a macro, defined in <code>stdio.h</code>.  You can use <code>getchar</code>
to get the next single character from the standard input stream.
As a side effect, <code>getchar</code> advances the standard input&rsquo;s
current position indicator.
</p>
<p>The alternate function <code>_getchar_r</code> is a reentrant version.  The
extra argument <var>reent</var> is a pointer to a reentrancy structure.
</p>
<br>
<p><strong>Returns</strong><br>
The next character (read as an <code>unsigned char</code>, and cast to
<code>int</code>), unless there is no more data, or the host system reports a
read error; in either of these situations, <code>getchar</code> returns <code>EOF</code>.
</p>
<p>You can distinguish the two situations that cause an <code>EOF</code> result by
using &lsquo;<code>ferror(stdin)</code>&rsquo; and &lsquo;<code>feof(stdin)</code>&rsquo;.
</p>
<br>
<p><strong>Portability</strong><br>
ANSI C requires <code>getchar</code>; it suggests, but does not require, that
<code>getchar</code> be implemented as a macro.
</p>
<p>Supporting OS subroutines required: <code>close</code>, <code>fstat</code>, <code>isatty</code>,
<code>lseek</code>, <code>read</code>, <code>sbrk</code>, <code>write</code>.
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