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<a name="GFORTRAN_005fUNBUFFERED_005fALL_002d_002d_002dDo-not-buffer-I_002fO-on-all-units"></a>
<h3 class="section">3.5 <code>GFORTRAN_UNBUFFERED_ALL</code>&mdash;Do not buffer I/O on all units</h3>

<p>This environment variable controls whether all I/O is unbuffered.  If
the first letter is &lsquo;<samp>y</samp>&rsquo;, &lsquo;<samp>Y</samp>&rsquo; or &lsquo;<samp>1</samp>&rsquo;, all I/O is
unbuffered.  This will slow down small sequential reads and writes.  If
the first letter is &lsquo;<samp>n</samp>&rsquo;, &lsquo;<samp>N</samp>&rsquo; or &lsquo;<samp>0</samp>&rsquo;, I/O is buffered.
This is the default.
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