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<a name="dprintf_002c-vdprintf_002d_002d_002dprint-to-a-file-descriptor"></a>
<h3 class="section">4.3 <code>dprintf</code>, <code>vdprintf</code>&mdash;print to a file descriptor</h3>
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<p><strong>Synopsis</strong>
</p><div class="example">
<pre class="example">#include &lt;stdio.h&gt;
#include &lt;stdarg.h&gt;
int dprintf(int <var>fd</var>, const char *restrict <var>format</var>, ...);
int vdprintf(int <var>fd</var>, const char *restrict <var>format</var>,
    va_list <var>ap</var>);
int _dprintf_r(struct _reent *<var>ptr</var>, int <var>fd</var>,
    const char *restrict <var>format</var>, ...);
int _vdprintf_r(struct _reent *<var>ptr</var>, int <var>fd</var>,
    const char *restrict <var>format</var>, va_list <var>ap</var>);

</pre></div>
<p><strong>Description</strong><br>
<code>dprintf</code> and <code>vdprintf</code> allow printing a format, similarly to
<code>printf</code>, but write to a file descriptor instead of to a <code>FILE</code>
stream.
</p>
<p>The functions <code>_dprintf_r</code> and <code>_vdprintf_r</code> are simply
reentrant versions of the functions above.
</p>
<br>
<p><strong>Returns</strong><br>
The return value and errors are exactly as for <code>write</code>, except that
<code>errno</code> may also be set to <code>ENOMEM</code> if the heap is exhausted.
</p>
<br>
<p><strong>Portability</strong><br>
This function is originally a GNU extension in glibc and is not portable.
</p>
<p>Supporting OS subroutines required: <code>sbrk</code>, <code>write</code>.
</p>
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