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<a name="fgetwc_002c-getwc_002c-fgetwc_005funlocked_002c-getwc_005funlocked_002d_002d_002dget-a-wide-character-from-a-file-or-stream"></a>
<h3 class="section">4.13 <code>fgetwc</code>, <code>getwc</code>, <code>fgetwc_unlocked</code>, <code>getwc_unlocked</code>&mdash;get a wide character from a file or stream</h3>
<a name="index-fgetwc"></a>
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<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t fgetwc(FILE *<var>fp</var>);

#define _GNU_SOURCE
#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t fgetwc_unlocked(FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t _fgetwc_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t _fgetwc_unlocked_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t getwc(FILE *<var>fp</var>);

#define _GNU_SOURCE
#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t getwc_unlocked(FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t _getwc_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

#include &lt;stdio.h&gt;
#include &lt;wchar.h&gt;
wint_t _getwc_unlocked_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

</pre></div>
<p><strong>Description</strong><br>
Use <code>fgetwc</code> to get the next wide character from the file or stream
identified by <var>fp</var>.  As a side effect, <code>fgetwc</code> advances the file&rsquo;s
current position indicator.
</p>
<p><code>fgetwc_unlocked</code> is a non-thread-safe version of <code>fgetwc</code>.
<code>fgetwc_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>fgetwc_unlocked</code> is equivalent to <code>fgetwc</code>.
</p>
<p>The <code>getwc</code> and <code>getwc_unlocked</code> functions or macros functions identically
to <code>fgetwc</code> and <code>fgetwc_unlocked</code>.  It may be implemented as a macro, and
may evaluate its argument more than once. There is no reason ever to use it.
</p>
<p><code>_fgetwc_r</code>, <code>_getwc_r</code>, <code>_fgetwc_unlocked_r</code>, and <code>_getwc_unlocked_r</code>
are simply reentrant versions of the above functions that are passed the
additional reentrant structure pointer argument: <var>ptr</var>.
</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>fgetwc</code> and <code>getwc</code> return <code>WEOF</code>.
</p>
<p>You can distinguish the two situations that cause an <code>EOF</code> result by
using the <code>ferror</code> and <code>feof</code> functions.
</p>
<br>
<p><strong>Portability</strong><br>
<code>fgetwc</code> and <code>getwc</code> are required by C99 and POSIX.1-2001.
</p>
<p><code>fgetwc_unlocked</code> and <code>getwc_unlocked</code> are GNU extensions.
</p>
<br>

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