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<h3 class="section">8.100 <code>GET_ENVIRONMENT_VARIABLE</code> — Get an environmental variable</h3>
<p><a name="index-GET_005fENVIRONMENT_005fVARIABLE-657"></a><a name="index-environment-variable-658"></a>
<dl>
<dt><em>Description</em>:<dd>Get the <var>VALUE</var> of the environmental variable <var>NAME</var>.
<p>Note that <code>GET_ENVIRONMENT_VARIABLE</code> need not be thread-safe. It
is the responsibility of the user to ensure that the environment is
not being updated concurrently with a call to the
<code>GET_ENVIRONMENT_VARIABLE</code> intrinsic.
<br><dt><em>Standard</em>:<dd>Fortran 2003 and later
<br><dt><em>Class</em>:<dd>Subroutine
<br><dt><em>Syntax</em>:<dd><code>CALL GET_ENVIRONMENT_VARIABLE(NAME[, VALUE, LENGTH, STATUS, TRIM_NAME)</code>
<br><dt><em>Arguments</em>:<dd>
<p><table summary=""><tr align="left"><td valign="top" width="15%"><var>NAME</var> </td><td valign="top" width="70%">Shall be a scalar of type <code>CHARACTER</code>
and of default kind.
<br></td></tr><tr align="left"><td valign="top" width="15%"><var>VALUE</var> </td><td valign="top" width="70%">(Optional) Shall be a scalar of type <code>CHARACTER</code>
and of default kind.
<br></td></tr><tr align="left"><td valign="top" width="15%"><var>LENGTH</var> </td><td valign="top" width="70%">(Optional) Shall be a scalar of type <code>INTEGER</code>
and of default kind.
<br></td></tr><tr align="left"><td valign="top" width="15%"><var>STATUS</var> </td><td valign="top" width="70%">(Optional) Shall be a scalar of type <code>INTEGER</code>
and of default kind.
<br></td></tr><tr align="left"><td valign="top" width="15%"><var>TRIM_NAME</var> </td><td valign="top" width="70%">(Optional) Shall be a scalar of type <code>LOGICAL</code>
and of default kind.
<br></td></tr></table>
<br><dt><em>Return value</em>:<dd>Stores the value of <var>NAME</var> in <var>VALUE</var>. If <var>VALUE</var> is
not large enough to hold the data, it is truncated. If <var>NAME</var>
is not set, <var>VALUE</var> will be filled with blanks. Argument <var>LENGTH</var>
contains the length needed for storing the environment variable <var>NAME</var>
or zero if it is not present. <var>STATUS</var> is -1 if <var>VALUE</var> is present
but too short for the environment variable; it is 1 if the environment
variable does not exist and 2 if the processor does not support environment
variables; in all other cases <var>STATUS</var> is zero. If <var>TRIM_NAME</var> is
present with the value <code>.FALSE.</code>, the trailing blanks in <var>NAME</var>
are significant; otherwise they are not part of the environment variable
name.
<br><dt><em>Example</em>:<dd>
<pre class="smallexample"> PROGRAM test_getenv
CHARACTER(len=255) :: homedir
CALL get_environment_variable("HOME", homedir)
WRITE (*,*) TRIM(homedir)
END PROGRAM
</pre>
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