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<a name="getc_005funlocked_002d_002d_002dnon_002dthread_002dsafe-version-of-getc-_0028macro_0029"></a>
<h3 class="section">4.34 <code>getc_unlocked</code>&mdash;non-thread-safe version of getc (macro)</h3>
<a name="index-getc_005funlocked"></a>
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<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include &lt;stdio.h&gt;
int getc_unlocked(FILE *<var>fp</var>);

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

</pre></div>
<p><strong>Description</strong><br>
<code>getc_unlocked</code> is a non-thread-safe version of <code>getc</code> declared in
<code>stdio.h</code>.  <code>getc_unlocked</code> may only safely be used within a scope
protected by flockfile() (or ftrylockfile()) and funlockfile().  These
functions 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>getc_unlocked</code> is equivalent to <code>getc</code>.
</p>
<p>The <code>_getc_unlocked_r</code> function is simply the reentrant version of
<code>get_unlocked</code> which passes an additional reentrancy structure pointer
argument: <var>ptr</var>.
</p>
<br>
<p><strong>Returns</strong><br>
See <code>getc</code>.
</p>
<br>
<p><strong>Portability</strong><br>
POSIX 1003.1 requires <code>getc_unlocked</code>.  <code>getc_unlocked</code> may be
implemented as a macro, so arguments should not have side-effects.
</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>.  
</p><br>


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