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            <h1>FindBin</h1>


  <!--    -->
<ul><li><a href="#NAME">NAME</a><li><a href="#SYNOPSIS">SYNOPSIS</a><li><a href="#DESCRIPTION">DESCRIPTION</a><li><a href="#EXPORTABLE-VARIABLES">EXPORTABLE VARIABLES</a><li><a href="#KNOWN-ISSUES">KNOWN ISSUES</a><li><a href="#KNOWN-BUGS">KNOWN BUGS</a><li><a href="#AUTHORS">AUTHORS</a><li><a href="#COPYRIGHT">COPYRIGHT</a></ul><a name="NAME"></a><h1>NAME</h1>
<p>FindBin - Locate directory of original perl script</p>
<a name="SYNOPSIS"></a><h1>SYNOPSIS</h1>
<pre class="verbatim"><ol><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">FindBin</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">lib</span> <span class="q">&quot;$FindBin::Bin/../lib&quot;</span><span class="sc">;</span></li><li></li><li> or</li><li></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">FindBin</span> <span class="q">qw($Bin)</span><span class="sc">;</span></li><li> <a class="l_k" href="functions/use.html">use</a> <span class="w">lib</span> <span class="q">&quot;$Bin/../lib&quot;</span><span class="sc">;</span></li></ol></pre><a name="DESCRIPTION"></a><h1>DESCRIPTION</h1>
<p>Locates the full path to the script bin directory to allow the use
of paths relative to the bin directory.</p>
<p>This allows a user to setup a directory tree for some software with
directories <code class="inline"><span class="q">&lt;root&gt;</span>/<span class="w">bin</span></code>
 and <code class="inline"><span class="q">&lt;root&gt;</span>/<span class="w">lib</span></code>
, and then the above
example will allow the use of modules in the lib directory without knowing
where the software tree is installed.</p>
<p>If perl is invoked using the <b>-e</b> option or the perl script is read from
<code class="inline"><span class="w">STDIN</span></code>
 then FindBin sets both <code class="inline"><span class="i">$Bin</span></code>
 and <code class="inline"><span class="i">$RealBin</span></code>
 to the current
directory.</p>
<a name="EXPORTABLE-VARIABLES"></a><h1>EXPORTABLE VARIABLES</h1>
<pre class="verbatim"><ol><li> $Bin         - path to bin directory from where script was invoked</li><li> $Script      - basename of script from which perl was invoked</li><li> $RealBin     - $Bin with all links resolved</li><li> $RealScript  - $Script with all links resolved</li></ol></pre><a name="KNOWN-ISSUES"></a><h1>KNOWN ISSUES</h1>
<p>If there are two modules using <code class="inline"><span class="w">FindBin</span></code>
 from different directories
under the same interpreter, this won't work. Since <code class="inline"><span class="w">FindBin</span></code>
 uses a
<code class="inline">BEGIN</code>
 block, it'll be executed only once, and only the first caller
will get it right. This is a problem under mod_perl and other persistent
Perl environments, where you shouldn't use this module. Which also means
that you should avoid using <code class="inline"><span class="w">FindBin</span></code>
 in modules that you plan to put
on CPAN. To make sure that <code class="inline"><span class="w">FindBin</span></code>
 will work is to call the <code class="inline"><span class="w">again</span></code>

function:</p>
<pre class="verbatim"><ol><li>  <a class="l_k" href="functions/use.html">use</a> <span class="w">FindBin</span><span class="sc">;</span></li><li>  <span class="i">FindBin::again</span><span class="s">(</span><span class="s">)</span><span class="sc">;</span> <span class="c"># or FindBin-&gt;again;</span></li></ol></pre><p>In former versions of FindBin there was no <code class="inline"><span class="w">again</span></code>
 function. The
workaround was to force the <code class="inline">BEGIN</code>
 block to be executed again:</p>
<pre class="verbatim"><ol><li>  <a class="l_k" href="functions/delete.html">delete</a> <span class="i">$INC</span>{<span class="q">&#39;FindBin.pm&#39;</span>}<span class="sc">;</span></li><li>  <a class="l_k" href="functions/require.html">require</a> <span class="w">FindBin</span><span class="sc">;</span></li></ol></pre><a name="KNOWN-BUGS"></a><h1>KNOWN BUGS</h1>
<p>If perl is invoked as</p>
<pre class="verbatim"><ol><li>   <span class="w">perl</span> <span class="w">filename</span></li></ol></pre><p>and <i>filename</i> does not have executable rights and a program called
<i>filename</i> exists in the users <code class="inline"><span class="i">$ENV</span>{<span class="w">PATH</span>}</code>
 which satisfies both <b>-x</b>
and <b>-T</b> then FindBin assumes that it was invoked via the
<code class="inline"><span class="i">$ENV</span>{<span class="w">PATH</span>}</code>
.</p>
<p>Workaround is to invoke perl as</p>
<pre class="verbatim"><ol><li> perl ./filename</li></ol></pre><a name="AUTHORS"></a><h1>AUTHORS</h1>
<p>FindBin is supported as part of the core perl distribution. Please send bug
reports to &lt;<i>perlbug@perl.org</i>&gt; using the perlbug program
included with perl.</p>
<p>Graham Barr &lt;<i>gbarr@pobox.com</i>&gt;
Nick Ing-Simmons &lt;<i>nik@tiuk.ti.com</i>&gt;</p>
<a name="COPYRIGHT"></a><h1>COPYRIGHT</h1>
<p>Copyright (c) 1995 Graham Barr &amp; Nick Ing-Simmons. All rights reserved.
This program is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.</p>




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