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<a name="getwchar_002c-getwchar_005funlocked_002d_002d_002dread-a-wide-character-from-standard-input"></a>
<h3 class="section">4.41 <code>getwchar</code>, <code>getwchar_unlocked</code>&mdash;read a wide character from standard input</h3>
<a name="index-getwchar"></a>
<a name="index-getwchar_005funlocked"></a>
<a name="index-_005fgetwchar_005fr"></a>
<a name="index-_005fgetwchar_005funlocked_005fr"></a>
<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include &lt;wchar.h&gt;
wint_t getwchar(void);

#define _GNU_SOURCE
#include &lt;wchar.h&gt;
wint_t getwchar_unlocked(void);

#include &lt;wchar.h&gt;
wint_t _getwchar_r(struct _reent *<var>reent</var>);

#include &lt;wchar.h&gt;
wint_t _getwchar_unlocked_r(struct _reent *<var>reent</var>);

</pre></div>
<p><strong>Description</strong><br>
<code>getwchar</code> function or macro is the wide character equivalent of
the <code>getchar</code> function.  You can use <code>getwchar</code> to get the next
wide character from the standard input stream.  As a side effect,
<code>getwchar</code> advances the standard input&rsquo;s current position indicator.
</p>
<p><code>getwchar_unlocked</code> is a non-thread-safe version of <code>getwchar</code>.
<code>getwchar_unlocked</code> may only safely be used within a scope
protected by flockfile() (or ftrylockfile()) and funlockfile().  This
function may safely be used in a multi-threaded program if and only
if they are called while the invoking thread owns the (FILE *)
object, as is the case after a successful call to the flockfile() or
ftrylockfile() functions.  If threads are disabled, then
<code>getwchar_unlocked</code> is equivalent to <code>getwchar</code>.
</p>
<p>The alternate functions <code>_getwchar_r</code> and <code>_getwchar_unlocked_r</code> are
reentrant versions of the above.  The extra argument <var>reent</var> is a pointer to
a reentrancy structure.
</p>
<br>
<p><strong>Returns</strong><br>
The next wide character cast to <code>wint_t</code>, unless there is no more
data, or the host system reports a read error; in either of these
situations, <code>getwchar</code> returns <code>WEOF</code>.
</p>
<p>You can distinguish the two situations that cause an <code>WEOF</code> result by
using &lsquo;<code>ferror(stdin)</code>&rsquo; and &lsquo;<code>feof(stdin)</code>&rsquo;.
</p>
<br>
<p><strong>Portability</strong><br>
<code>getwchar</code> is required by C99.
</p>
<p><code>getwchar_unlocked</code> is a GNU extension.
</p>
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