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<a name="fgetc_002c-fgetc_005funlocked_002d_002d_002dget-a-character-from-a-file-or-stream"></a>
<h3 class="section">4.10 <code>fgetc</code>, <code>fgetc_unlocked</code>&mdash;get a character from a file or stream</h3>
<a name="index-fgetc"></a>
<a name="index-fgetc_005funlocked"></a>
<a name="index-_005ffgetc_005fr"></a>
<a name="index-_005ffgetc_005funlocked_005fr"></a>
<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include &lt;stdio.h&gt;
int fgetc(FILE *<var>fp</var>);

#define _BSD_SOURCE
#include &lt;stdio.h&gt;
int fgetc_unlocked(FILE *<var>fp</var>);

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

#define _BSD_SOURCE
#include &lt;stdio.h&gt;
int _fgetc_unlocked_r(struct _reent *<var>ptr</var>, FILE *<var>fp</var>);

</pre></div>
<p><strong>Description</strong><br>
Use <code>fgetc</code> to get the next single character from the file or stream
identified by <var>fp</var>.  As a side effect, <code>fgetc</code> advances the file&rsquo;s
current position indicator.
</p>
<p>For a macro version of this function, see <code>getc</code>.
</p>
<p><code>fgetc_unlocked</code> is a non-thread-safe version of <code>fgetc</code>.
<code>fgetc_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>fgetc_unlocked</code> is equivalent to <code>fgetc</code>.
</p>
<p>The functions <code>_fgetc_r</code> and <code>_fgetc_unlocked_r</code> are simply reentrant
versions that are passed the additional reentrant structure pointer
argument: <var>ptr</var>.
</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>fgetc</code> returns <code>EOF</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>
ANSI C requires <code>fgetc</code>.
</p>
<p><code>fgetc_unlocked</code> is a BSD extension also provided by GNU libc.
</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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