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<title>Qp0zGetEnv()--Get Value of Environment Variable (Extended)</title>
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<h2>Qp0zGetEnv()--Get Value of Environment Variable (Extended)</h2>
<div class="box" style="width: 60%;">
<br>
&nbsp;&nbsp;Syntax
<pre>
#include &lt;qp0z1170.h&gt;
char *Qp0zGetEnv(const char <em>*name</em>, int <em>*ccsid</em>);
</pre>
&nbsp;&nbsp;Service Program Name: QP0ZCPA<br>
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<br>
&nbsp;&nbsp;Default Public Authority: *USE<br>
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&nbsp;&nbsp;Threadsafe: Yes. See Usage Notes for more information.<br>
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</div>
<p>The <strong>Qp0zGetEnv()</strong> function is an i5/OS extension to the
standard <strong>getenv()</strong> function. <strong>Qp0zGetEnv()</strong>
searches the job-level environment list for a string of the form <samp>
name=value</samp>. The <samp>value</samp> and the CCSID (coded character set
identifier) associated with the environment variable <samp>name</samp> are
returned.</p>
<br>
<!-- Please NOTE: DO NOT DELETE THIS SECTION if this API has no authorities and locks. -->
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<h3>Authorities and Locks</h3>
<!-- Use this if there are no authorities and locks. -->
<p>None.</p>
<br>
<h3>Parameters</h3>
<dl>
<dt><strong><em>name</em></strong></dt>
<dd>(Input) The name of an environment variable.<br>
</dd>
<dt><strong><em>ccsid</em></strong></dt>
<dd>(Output) The CCSID for the named environment variable.</dd>
</dl>
<br>
<h3>Return Value</h3>
<table cellpadding="5">
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<tr>
<td align="left" valign="top"><em>value</em></td>
<td align="left" valign="top"><strong>Qp0zGetEnv()</strong> successfully found
the environment string. The value returned is a pointer to the string
containing the <samp>value</samp> for the specified <samp>name</samp> in the
current environment.</td>
</tr>
<tr>
<td align="left" valign="top"><em>NULL</em></td>
<td align="left" valign="top"><strong>Qp0zGetEnv()</strong> could not find the
environment string. The <em>errno</em> variable is set to indicate the
error.</td>
</tr>
</table>
<br>
<br>
<h3>Error Conditions</h3>
<p>If <strong>Qp0zGetEnv()</strong> is not successful, <em>errno</em> indicates
one of the following errors.</p>
<dl compact>
<dt><em>[EDAMAGE]</em></dt>
<dd>
<p>A damaged object was encountered.</p>
<p>A referenced object is damaged. The object cannot be used.</p>
</dd>
<dt><em>[EFAULT]</em></dt>
<dd>
<p>The address used for an argument is not correct.</p>
<p>In attempting to use an argument in a call, the system detected an address
that is not valid.</p>
<p>While attempting to access a parameter passed to this function, the system
detected an address that is not valid.</p>
</dd>
<dt><em>[ENOENT]</em></dt>
<dd>
<p>No such path or directory.</p>
<p>The directory or a component of the path name specified does not exist.</p>
<p>A named file or directory does not exist or is an empty string.</p>
<p>No entry found for name specified.</p>
</dd>
<dt><em>[EUNKNOWN]</em></dt>
<dd>
<p>Unknown system state.</p>
<p>The operation failed because of an unknown system state. See any messages in
the job log and correct any errors that are indicated, then retry the
operation.</p>
</dd>
</dl>
<br>
<h3>Usage Notes</h3>
<ol>
<li>Although <strong>Qp0zGetEnv()</strong> is threadsafe, if a thread calls an
environment variable function while another thread is accessing an environment
variable from the environ array the thread may see undefined results. The
environ array can be accessed directly or by using a pointer returned from the
<strong>getenv()</strong> or <strong>Qp0zGetEnv()</strong> functions. The
environment contents are only protected during calls to the environment
variable functions.<br>
</li>
<li>No translation is done based on the CCSID. The CCSID is just stored and
retrieved as an integer value associated with each environment variable.</li>
</ol>
<br>
<h3>Related Information</h3>
<ul>
<li>The &lt;<strong>qp0z1170.h</strong>&gt; file (see <a href="unix13.htm">
Header Files for UNIX-Type Functions</a>)</li>
<li><a href="evgetenv.htm">getenv()</a>--Get Value of Environment Variable</li>
<li><a href="evputenv.htm">putenv()</a>--Change or Add Environment
Variable</li>
<li><a href="evdltenv.htm">Qp0zDltEnv()</a>--Delete an Environment
Variable</li>
<li><a href="evdltsev.htm">Qp0zDltSysEnv()</a>--Delete a System-Level
Environment Variable</li>
<li><a href="evgetall.htm">Qp0zGetAllSysEnv()</a>--Get All System-Level
Environment Variables</li>
<li><a href="evgetsev.htm">Qp0zGetSysEnv()</a>--Get Value of System-Level
Environment Variable</li>
<li><a href="evinenv.htm">Qp0zInitEnv()</a>--Initialize Environment for
Variables</li>
<li><a href="evpenvxt.htm">Qp0zPutEnv()</a>--Change or Add Environment Variable
(Extended)</li>
<li><a href="evputsev.htm">Qp0zPutSysEnv()</a>--Change or Add a System-Level
Environment</li>
</ul>
<br>
<h3>Example</h3>
<p>See <a href="../apiref/aboutapis.htm#codedisclaimer">Code disclaimer information</a>
for information pertaining to code examples.</p>
<p>See the example of using <strong>getenv()</strong> in <a href=
"evputenv.htm">putenv()</a>--Change or Add Environment Variable.</p>
<br>
<hr>
API introduced: V3R6
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