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<title>The GNU Fortran Compiler: ACCESS</title>

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<p>
Next: <a href="ACHAR.html#ACHAR" accesskey="n" rel="next">ACHAR</a>, Previous: <a href="ABS.html#ABS" accesskey="p" rel="prev">ABS</a>, Up: <a href="Intrinsic-Procedures.html#Intrinsic-Procedures" accesskey="u" rel="up">Intrinsic Procedures</a> &nbsp; [<a href="index.html#SEC_Contents" title="Table of contents" rel="contents">Contents</a>][<a href="Option-Index.html#Option-Index" title="Index" rel="index">Index</a>]</p>
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<hr>
<a name="ACCESS-_002d_002d_002d-Checks-file-access-modes"></a>
<h3 class="section">9.4 <code>ACCESS</code> &mdash; Checks file access modes</h3>
<a name="index-ACCESS"></a>
<a name="index-file-system_002c-access-mode"></a>

<dl compact="compact">
<dt><em>Description</em>:</dt>
<dd><p><code>ACCESS(NAME, MODE)</code> checks whether the file <var>NAME</var> 
exists, is readable, writable or executable. Except for the
executable check, <code>ACCESS</code> can be replaced by
Fortran 95&rsquo;s <code>INQUIRE</code>.
</p>
</dd>
<dt><em>Standard</em>:</dt>
<dd><p>GNU extension
</p>
</dd>
<dt><em>Class</em>:</dt>
<dd><p>Inquiry function
</p>
</dd>
<dt><em>Syntax</em>:</dt>
<dd><p><code>RESULT = ACCESS(NAME, MODE)</code>
</p>
</dd>
<dt><em>Arguments</em>:</dt>
<dd><table>
<tr><td width="15%"><var>NAME</var></td><td width="70%">Scalar <code>CHARACTER</code> of default kind with the
file name. Tailing blank are ignored unless the character <code>achar(0)</code>
is present, then all characters up to and excluding <code>achar(0)</code> are
used as file name.</td></tr>
<tr><td width="15%"><var>MODE</var></td><td width="70%">Scalar <code>CHARACTER</code> of default kind with the
file access mode, may be any concatenation of <code>&quot;r&quot;</code> (readable),
<code>&quot;w&quot;</code> (writable) and <code>&quot;x&quot;</code> (executable), or <code>&quot; &quot;</code> to check
for existence.</td></tr>
</table>

</dd>
<dt><em>Return value</em>:</dt>
<dd><p>Returns a scalar <code>INTEGER</code>, which is <code>0</code> if the file is
accessible in the given mode; otherwise or if an invalid argument
has been given for <code>MODE</code> the value <code>1</code> is returned.
</p>
</dd>
<dt><em>Example</em>:</dt>
<dd><div class="smallexample">
<pre class="smallexample">program access_test
  implicit none
  character(len=*), parameter :: file  = 'test.dat'
  character(len=*), parameter :: file2 = 'test.dat  '//achar(0)
  if(access(file,' ') == 0) print *, trim(file),' is exists'
  if(access(file,'r') == 0) print *, trim(file),' is readable'
  if(access(file,'w') == 0) print *, trim(file),' is writable'
  if(access(file,'x') == 0) print *, trim(file),' is executable'
  if(access(file2,'rwx') == 0) &amp;
    print *, trim(file2),' is readable, writable and executable'
end program access_test
</pre></div>
</dd>
<dt><em>Specific names</em>:</dt>
<dt><em>See also</em>:</dt>
</dl>


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