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<li><a href="http://www.perl.org">Perl.org</a></li>
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<li><a href="http://planet.perl.org">Planet Perl</a></li>
<li><a href="http://use.perl.org">Use Perl</a></li>
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<div id="contentBody"><div class="title_container"><div class="page_title">perl</div></div><ul><li><a href="#NAME">NAME</a><li><a href="#SYNOPSIS">SYNOPSIS</a><ul><li><a href="#Overview">Overview</a><li><a href="#Tutorials">Tutorials</a><li><a href="#Reference-Manual">Reference Manual</a><li><a href="#Internals-and-C-Language-Interface">Internals and C Language Interface</a><li><a href="#Miscellaneous">Miscellaneous</a><li><a href="#Language-Specific">Language-Specific</a><li><a href="#Platform-Specific">Platform-Specific</a></ul><li><a href="#DESCRIPTION">DESCRIPTION</a><li><a href="#AVAILABILITY">AVAILABILITY</a><li><a href="#ENVIRONMENT">ENVIRONMENT</a><li><a href="#AUTHOR">AUTHOR</a><li><a href="#FILES">FILES</a><li><a href="#SEE-ALSO">SEE ALSO</a><li><a href="#DIAGNOSTICS">DIAGNOSTICS</a><li><a href="#BUGS">BUGS</a><li><a href="#NOTES">NOTES</a></ul><a name="NAME"></a><h1>NAME</h1>
<p>perl - Practical Extraction and Report Language</p>
<a name="SYNOPSIS"></a><h1>SYNOPSIS</h1>
<p><b>perl</b> [ <b>-sTtuUWX</b> ]
[ <b>-hv</b> ] [ <b>-V</b>[:<i>configvar</i>] ]
[ <b>-cw</b> ] [ <b>-d</b>[<b>t</b>][:<i>debugger</i>] ] [ <b>-D</b>[<i>number/list</i>] ]
[ <b>-pna</b> ] [ <b>-F</b><i>pattern</i> ] [ <b>-l</b>[<i>octal</i>] ] [ <b>-0</b>[<i>octal/hexadecimal</i>] ]
[ <b>-I</b><i>dir</i> ] [ <b>-m</b>[<b>-</b>]<i>module</i> ] [ <b>-M</b>[<b>-</b>]<i>'module...'</i> ] [ <b>-f</b> ]
[ <b>-C [<i>number/list</i>] </b>]
[ <b>-P</b> ]
[ <b>-S</b> ]
[ <b>-x</b>[<i>dir</i>] ]
[ <b>-i</b>[<i>extension</i>] ]
[ <b>-e</b> <i>'command'</i> ] [ <b>--</b> ] [ <i>programfile</i> ] [ <i>argument</i> ]...</p>
<p>If you're new to Perl, you should start with <a href="perlintro.html">perlintro</a>, which is a
general intro for beginners and provides some background to help you
navigate the rest of Perl's extensive documentation.</p>
<p>For ease of access, the Perl manual has been split up into several sections.</p>
<a name="Overview"></a><h2>Overview</h2>
<pre class="verbatim"> perl Perl overview (this section)
<a href="perlintro.html">perlintro</a> Perl introduction for beginners
perltoc Perl documentation table of contents</pre><a name="Tutorials"></a><h2>Tutorials</h2>
<pre class="verbatim"> <a href="perlreftut.html">perlreftut</a> Perl references short introduction
<a href="perldsc.html">perldsc</a> Perl data structures intro
<a href="perllol.html">perllol</a> Perl data structures: arrays of arrays</pre><pre class="verbatim"> <span class="w"><a href="perlrequick.html">perlrequick</a></span> <span class="w">Perl</span> <span class="w">regular</span> <span class="w">expressions</span> <span class="w">quick</span> <span class="w">start</span>
<span class="w"><a href="perlretut.html">perlretut</a></span> <span class="w">Perl</span> <span class="w">regular</span> <span class="w">expressions</span> <span class="w">tutorial</span></pre>
<pre class="verbatim"> <a href="perlboot.html">perlboot</a> Perl OO tutorial for beginners
<a href="perltoot.html">perltoot</a> Perl OO tutorial, part 1
<a href="perltooc.html">perltooc</a> Perl OO tutorial, part 2
<a href="perlbot.html">perlbot</a> Perl OO tricks and examples</pre><pre class="verbatim"> <span class="w"><a href="perlstyle.html">perlstyle</a></span> <span class="w">Perl</span> <span class="w">style</span> <span class="w">guide</span></pre>
<pre class="verbatim"> <span class="w"><a href="perlcheat.html">perlcheat</a></span> <span class="w">Perl</span> <span class="w">cheat</span> <span class="w">sheet</span>
<span class="w"><a href="perltrap.html">perltrap</a></span> <span class="w">Perl</span> <span class="w">traps</span> for <span class="w">the</span> <span class="w">unwary</span>
<span class="w"><a href="perldebtut.html">perldebtut</a></span> <span class="w">Perl</span> <span class="w">debugging</span> <span class="w">tutorial</span></pre>
<pre class="verbatim"> <span class="w"><a href="perlfaq.html">perlfaq</a></span> <span class="w">Perl</span> <span class="w">frequently</span> <span class="w">asked</span> <span class="w">questions</span>
<span class="w"><a href="perlfaq1.html">perlfaq1</a></span> <span class="w">General</span> <span class="w">Questions</span> <span class="w">About</span> <span class="w">Perl</span>
<span class="w"><a href="perlfaq2.html">perlfaq2</a></span> <span class="w">Obtaining</span> and <span class="w">Learning</span> <span class="w">about</span> <span class="w">Perl</span>
<span class="w"><a href="perlfaq3.html">perlfaq3</a></span> <span class="w">Programming</span> <span class="w">Tools</span>
<span class="w"><a href="perlfaq4.html">perlfaq4</a></span> <span class="w">Data</span> <span class="w">Manipulation</span>
<span class="w"><a href="perlfaq5.html">perlfaq5</a></span> <span class="w">Files</span> and <span class="w">Formats</span>
<span class="w"><a href="perlfaq6.html">perlfaq6</a></span> <span class="w">Regexes</span>
<span class="w"><a href="perlfaq7.html">perlfaq7</a></span> <span class="w">Perl</span> <span class="w">Language</span> <span class="w">Issues</span>
<span class="w"><a href="perlfaq8.html">perlfaq8</a></span> <span class="w">System</span> <span class="w">Interaction</span>
<span class="w"><a href="perlfaq9.html">perlfaq9</a></span> <span class="w">Networking</span></pre>
<a name="Reference-Manual"></a><h2>Reference Manual</h2>
<pre class="verbatim"> <a href="perlsyn.html">perlsyn</a> Perl syntax
<a href="perldata.html">perldata</a> Perl data structures
<a href="perlop.html">perlop</a> Perl operators and precedence
<a href="perlsub.html">perlsub</a> Perl subroutines
<a href="perlfunc.html">perlfunc</a> Perl built-in functions
<a href="perlopentut.html">perlopentut</a> Perl open() tutorial
<a href="perlpacktut.html">perlpacktut</a> Perl pack() and unpack() tutorial
<a href="perlpod.html">perlpod</a> Perl plain old documentation
<a href="perlpodspec.html">perlpodspec</a> Perl plain old documentation format specification
<a href="perlrun.html">perlrun</a> Perl execution and options
<a href="perldiag.html">perldiag</a> Perl diagnostic messages
<a href="perllexwarn.html">perllexwarn</a> Perl warnings and their control
<a href="perldebug.html">perldebug</a> Perl debugging
<a href="perlvar.html">perlvar</a> Perl predefined variables
<a href="perlre.html">perlre</a> Perl regular expressions, the rest of the story
<a href="perlrebackslash.html">perlrebackslash</a> Perl regular expression backslash sequences
<a href="perlrecharclass.html">perlrecharclass</a> Perl regular expression character classes
<a href="perlreref.html">perlreref</a> Perl regular expressions quick reference
<a href="perlref.html">perlref</a> Perl references, the rest of the story
<a href="perlform.html">perlform</a> Perl formats
<a href="perlobj.html">perlobj</a> Perl objects
<a href="perltie.html">perltie</a> Perl objects hidden behind simple variables
<a href="perldbmfilter.html">perldbmfilter</a> Perl DBM filters</pre><pre class="verbatim"> <a href="perlipc.html">perlipc</a> Perl interprocess communication
<a href="perlfork.html">perlfork</a> Perl fork() information
<a href="perlnumber.html">perlnumber</a> Perl number semantics</pre><pre class="verbatim"> <span class="w"><a href="perlthrtut.html">perlthrtut</a></span> <span class="w">Perl</span> <span class="w">threads</span> <span class="w">tutorial</span>
<span class="w"><a href="perlothrtut.html">perlothrtut</a></span> <span class="w">Old</span> <span class="w">Perl</span> <span class="w">threads</span> <span class="w">tutorial</span></pre>
<pre class="verbatim"> <span class="w"><a href="perlport.html">perlport</a></span> <span class="w">Perl</span> <span class="w">portability</span> <span class="w">guide</span>
<span class="w"><a href="perllocale.html">perllocale</a></span> <span class="w">Perl</span> <span class="w">locale</span> <span class="w">support</span>
<span class="w"><a href="perluniintro.html">perluniintro</a></span> <span class="w">Perl</span> <span class="w">Unicode</span> <span class="w">introduction</span>
<span class="w"><a href="perlunicode.html">perlunicode</a></span> <span class="w">Perl</span> <span class="w">Unicode</span> <span class="w">support</span>
<span class="w"><a href="perlunifaq.html">perlunifaq</a></span> <span class="w">Perl</span> <span class="w">Unicode</span> <span class="w">FAQ</span>
<span class="w"><a href="perlunitut.html">perlunitut</a></span> <span class="w">Perl</span> <span class="w">Unicode</span> <span class="w">tutorial</span>
<span class="w"><a href="perlebcdic.html">perlebcdic</a></span> <span class="w">Considerations</span> for <span class="w">running</span> <span class="w">Perl</span> <span class="w">on</span> <span class="w">EBCDIC</span> <span class="w">platforms</span></pre>
<pre class="verbatim"> <span class="w"><a href="perlsec.html">perlsec</a></span> <span class="w">Perl</span> <span class="w">security</span></pre>
<pre class="verbatim"> <a href="perlmod.html">perlmod</a> Perl modules: how they work
<a href="perlmodlib.html">perlmodlib</a> Perl modules: how to write and use
<a href="perlmodstyle.html">perlmodstyle</a> Perl modules: how to write modules with style
<a href="perlmodinstall.html">perlmodinstall</a> Perl modules: how to install from CPAN
<a href="perlnewmod.html">perlnewmod</a> Perl modules: preparing a new module for distribution
<a href="perlpragma.html">perlpragma</a> Perl modules: writing a user pragma</pre><pre class="verbatim"> <span class="w"><a href="perlutil.html">perlutil</a></span> <span class="w">utilities</span> <span class="w">packaged</span> <span class="w">with</span> <span class="w">the</span> <span class="w">Perl</span> <span class="w">distribution</span></pre>
<pre class="verbatim"> <span class="w"><a href="perlcompile.html">perlcompile</a></span> <span class="w">Perl</span> <span class="w">compiler</span> <span class="w">suite</span> <span class="w">intro</span></pre>
<pre class="verbatim"> <span class="w"><a href="perlfilter.html">perlfilter</a></span> <span class="w">Perl</span> <span class="w">source</span> <span class="w">filters</span></pre>
<pre class="verbatim"> <span class="w"><a href="perlglossary.html">perlglossary</a></span> <span class="w">Perl</span> <span class="w">Glossary</span></pre>
<a name="Internals-and-C-Language-Interface"></a><h2>Internals and C Language Interface</h2>
<pre class="verbatim"> <a href="perlembed.html">perlembed</a> Perl ways to embed perl in your C or C++ application
<a href="perldebguts.html">perldebguts</a> Perl debugging guts and tips
<a href="perlxstut.html">perlxstut</a> Perl XS tutorial
<a href="perlxs.html">perlxs</a> Perl XS application programming interface
<a href="perlclib.html">perlclib</a> Internal replacements for standard C library functions
<a href="perlguts.html">perlguts</a> Perl internal functions for those doing extensions
<a href="perlcall.html">perlcall</a> Perl calling conventions from C
<a href="perlreapi.html">perlreapi</a> Perl regular expression plugin interface
<a href="perlreguts.html">perlreguts</a> Perl regular expression engine internals</pre><pre class="verbatim"> <a href="perlapi.html">perlapi</a> Perl API listing (autogenerated)
<a href="perlintern.html">perlintern</a> Perl internal functions (autogenerated)
<a href="perliol.html">perliol</a> C API for Perl's implementation of IO in Layers
<a href="perlapio.html">perlapio</a> Perl internal IO abstraction interface</pre><pre class="verbatim"> <span class="w"><a href="perlhack.html">perlhack</a></span> <span class="w">Perl</span> <span class="w">hackers</span> <span class="w">guide</span></pre>
<a name="Miscellaneous"></a><h2>Miscellaneous</h2>
<pre class="verbatim"> <span class="w"><a href="perlbook.html">perlbook</a></span> <span class="w">Perl</span> <span class="w">book</span> <span class="w">information</span>
<span class="w"><a href="perlcommunity.html">perlcommunity</a></span> <span class="w">Perl</span> <span class="w">community</span> <span class="w">information</span>
<span class="w"><a href="perltodo.html">perltodo</a></span> <span class="w">Perl</span> <span class="w">things</span> <span class="w">to</span> <a class="l_k" href="functions/do.html">do</a></pre>
<pre class="verbatim"> <a href="perldoc.html">perldoc</a> Look up Perl documentation in Pod format</pre><pre class="verbatim"> <a href="perlhist.html">perlhist</a> Perl history records
<a href="perldelta.html">perldelta</a> Perl changes since previous version
<a href="perl595delta.html">perl595delta</a> Perl changes in version 5.9.5
<a href="perl594delta.html">perl594delta</a> Perl changes in version 5.9.4
<a href="perl593delta.html">perl593delta</a> Perl changes in version 5.9.3
<a href="perl592delta.html">perl592delta</a> Perl changes in version 5.9.2
<a href="perl591delta.html">perl591delta</a> Perl changes in version 5.9.1
<a href="perl590delta.html">perl590delta</a> Perl changes in version 5.9.0
<a href="perl588delta.html">perl588delta</a> Perl changes in version 5.8.8
<a href="perl587delta.html">perl587delta</a> Perl changes in version 5.8.7
<a href="perl586delta.html">perl586delta</a> Perl changes in version 5.8.6
<a href="perl585delta.html">perl585delta</a> Perl changes in version 5.8.5
<a href="perl584delta.html">perl584delta</a> Perl changes in version 5.8.4
<a href="perl583delta.html">perl583delta</a> Perl changes in version 5.8.3
<a href="perl582delta.html">perl582delta</a> Perl changes in version 5.8.2
<a href="perl581delta.html">perl581delta</a> Perl changes in version 5.8.1
<a href="perl58delta.html">perl58delta</a> Perl changes in version 5.8.0
<a href="perl573delta.html">perl573delta</a> Perl changes in version 5.7.3
<a href="perl572delta.html">perl572delta</a> Perl changes in version 5.7.2
<a href="perl571delta.html">perl571delta</a> Perl changes in version 5.7.1
<a href="perl570delta.html">perl570delta</a> Perl changes in version 5.7.0
<a href="perl561delta.html">perl561delta</a> Perl changes in version 5.6.1
<a href="perl56delta.html">perl56delta</a> Perl changes in version 5.6
<a href="perl5005delta.html">perl5005delta</a> Perl changes in version 5.005
<a href="perl5004delta.html">perl5004delta</a> Perl changes in version 5.004</pre><pre class="verbatim"> <span class="w"><a href="perlartistic.html">perlartistic</a></span> <span class="w">Perl</span> <span class="w">Artistic</span> <span class="w">License</span>
<span class="w"><a href="perlgpl.html">perlgpl</a></span> <span class="w">GNU</span> <span class="w">General</span> <span class="w">Public</span> <span class="w">License</span></pre>
<a name="Language-Specific"></a><h2>Language-Specific</h2>
<pre class="verbatim"> perlcn Perl for Simplified Chinese (in EUC-CN)
perljp Perl for Japanese (in EUC-JP)
perlko Perl for Korean (in EUC-KR)
perltw Perl for Traditional Chinese (in Big5)</pre><a name="Platform-Specific"></a><h2>Platform-Specific</h2>
<pre class="verbatim"> <a href="perlaix.html">perlaix</a> Perl notes for AIX
<a href="perlamiga.html">perlamiga</a> Perl notes for AmigaOS
<a href="perlapollo.html">perlapollo</a> Perl notes for Apollo DomainOS
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<a href="perlvos.html">perlvos</a> Perl notes for Stratus VOS
<a href="perlwin32.html">perlwin32</a> Perl notes for Windows</pre><p>By default, the manpages listed above are installed in the
<i>/usr/local/man/</i> directory.</p>
<p>Extensive additional documentation for Perl modules is available. The
default configuration for perl will place this additional documentation
in the <i>/usr/local/lib/perl5/man</i> directory (or else in the <i>man</i>
subdirectory of the Perl library directory). Some of this additional
documentation is distributed standard with Perl, but you'll also find
documentation for third-party modules there.</p>
<p>You should be able to view Perl's documentation with your man(1)
program by including the proper directories in the appropriate start-up
files, or in the MANPATH environment variable. To find out where the
configuration has installed the manpages, type:</p>
<pre class="verbatim"> perl -V:man.dir</pre><p>If the directories have a common stem, such as <i>/usr/local/man/man1</i>
and <i>/usr/local/man/man3</i>, you need only to add that stem
(<i>/usr/local/man</i>) to your man(1) configuration files or your MANPATH
environment variable. If they do not share a stem, you'll have to add
both stems.</p>
<p>If that doesn't work for some reason, you can still use the
supplied <i>perldoc</i> script to view module information. You might
also look into getting a replacement man program.</p>
<p>If something strange has gone wrong with your program and you're not
sure where you should look for help, try the <b>-w</b> switch first. It
will often point out exactly where the trouble is.</p>
<a name="DESCRIPTION"></a><h1>DESCRIPTION</h1>
<p>Perl is a language optimized for scanning arbitrary
text files, extracting information from those text files, and printing
reports based on that information. It's also a good language for many
system management tasks. The language is intended to be practical
(easy to use, efficient, complete) rather than beautiful (tiny,
elegant, minimal).</p>
<p>Perl combines (in the author's opinion, anyway) some of the best
features of C, <b>sed</b>, <b>awk</b>, and <b>sh</b>, so people familiar with
those languages should have little difficulty with it. (Language
historians will also note some vestiges of <b>csh</b>, Pascal, and even
BASIC-PLUS.) Expression syntax corresponds closely to C
expression syntax. Unlike most Unix utilities, Perl does not
arbitrarily limit the size of your data--if you've got the memory,
Perl can slurp in your whole file as a single string. Recursion is of
unlimited depth. And the tables used by hashes (sometimes called
"associative arrays") grow as necessary to prevent degraded
performance. Perl can use sophisticated pattern matching techniques to
scan large amounts of data quickly. Although optimized for
scanning text, Perl can also deal with binary data, and can make dbm
files look like hashes. Setuid Perl scripts are safer than C programs
through a dataflow tracing mechanism that prevents many stupid
security holes.</p>
<p>If you have a problem that would ordinarily use <b>sed</b> or <b>awk</b> or
<b>sh</b>, but it exceeds their capabilities or must run a little faster,
and you don't want to write the silly thing in C, then Perl may be for
you. There are also translators to turn your <b>sed</b> and <b>awk</b>
scripts into Perl scripts.</p>
<p>But wait, there's more...</p>
<p>Begun in 1993 (see <a href="perlhist.html">perlhist</a>), Perl version 5 is nearly a complete
rewrite that provides the following additional benefits:</p>
<ul>
<li>
<p>modularity and reusability using innumerable modules</p>
<p>Described in <a href="perlmod.html">perlmod</a>, <a href="perlmodlib.html">perlmodlib</a>, and <a href="perlmodinstall.html">perlmodinstall</a>.</p>
</li>
<li>
<p>embeddable and extensible</p>
<p>Described in <a href="perlembed.html">perlembed</a>, <a href="perlxstut.html">perlxstut</a>, <a href="perlxs.html">perlxs</a>, <a href="perlcall.html">perlcall</a>,
<a href="perlguts.html">perlguts</a>, and <a href="xsubpp.html">xsubpp</a>.</p>
</li>
<li>
<p>roll-your-own magic variables (including multiple simultaneous DBM
implementations)</p>
<p>Described in <a href="perltie.html">perltie</a> and <a href="AnyDBM_File.html">AnyDBM_File</a>.</p>
</li>
<li>
<p>subroutines can now be overridden, autoloaded, and prototyped</p>
<p>Described in <a href="perlsub.html">perlsub</a>.</p>
</li>
<li>
<p>arbitrarily nested data structures and anonymous functions</p>
<p>Described in <a href="perlreftut.html">perlreftut</a>, <a href="perlref.html">perlref</a>, <a href="perldsc.html">perldsc</a>, and <a href="perllol.html">perllol</a>.</p>
</li>
<li>
<p>object-oriented programming</p>
<p>Described in <a href="perlobj.html">perlobj</a>, <a href="perlboot.html">perlboot</a>, <a href="perltoot.html">perltoot</a>, <a href="perltooc.html">perltooc</a>,
and <a href="perlbot.html">perlbot</a>.</p>
</li>
<li>
<p>support for light-weight processes (threads)</p>
<p>Described in <a href="perlthrtut.html">perlthrtut</a> and <a href="threads.html">threads</a>.</p>
</li>
<li>
<p>support for Unicode, internationalization, and localization</p>
<p>Described in <a href="perluniintro.html">perluniintro</a>, <a href="perllocale.html">perllocale</a> and <a href="Locale/Maketext.html">Locale::Maketext</a>.</p>
</li>
<li>
<p>lexical scoping</p>
<p>Described in <a href="perlsub.html">perlsub</a>.</p>
</li>
<li>
<p>regular expression enhancements</p>
<p>Described in <a href="perlre.html">perlre</a>, with additional examples in <a href="perlop.html">perlop</a>.</p>
</li>
<li>
<p>enhanced debugger and interactive Perl environment,
with integrated editor support</p>
<p>Described in <a href="perldebtut.html">perldebtut</a>, <a href="perldebug.html">perldebug</a> and <a href="perldebguts.html">perldebguts</a>.</p>
</li>
<li>
<p>POSIX 1003.1 compliant library</p>
<p>Described in <a href="POSIX.html">POSIX</a>.</p>
</li>
</ul>
<p>Okay, that's <i>definitely</i> enough hype.</p>
<a name="AVAILABILITY"></a><h1>AVAILABILITY</h1>
<p>Perl is available for most operating systems, including virtually
all Unix-like platforms. See <a href="perlport.html#Supported-Platforms">"Supported Platforms" in perlport</a>
for a listing.</p>
<a name="ENVIRONMENT"></a><h1>ENVIRONMENT</h1>
<p>See <a href="perlrun.html">perlrun</a>.</p>
<a name="AUTHOR"></a><h1>AUTHOR</h1>
<p>Larry Wall <larry@wall.org>, with the help of oodles of other folks.</p>
<p>If your Perl success stories and testimonials may be of help to others
who wish to advocate the use of Perl in their applications,
or if you wish to simply express your gratitude to Larry and the
Perl developers, please write to perl-thanks@perl.org .</p>
<a name="FILES"></a><h1>FILES</h1>
<pre class="verbatim"> "@INC" locations of perl libraries</pre><a name="SEE-ALSO"></a><h1>SEE ALSO</h1>
<pre class="verbatim"> <span class="w">a2p</span> <span class="w">awk</span> <span class="w">to</span> <span class="w">perl</span> <span class="w">translator</span>
<span class="w">s2p</span> <span class="w">sed</span> <span class="w">to</span> <span class="w">perl</span> <span class="w">translator</span></pre>
<pre class="verbatim"> http://www.perl.org/ the Perl homepage
http://www.perl.com/ Perl articles (O'Reilly)
http://www.cpan.org/ the Comprehensive Perl Archive
http://www.pm.org/ the Perl Mongers</pre><a name="DIAGNOSTICS"></a><h1>DIAGNOSTICS</h1>
<p>The <code class="inline"><a class="l_k" href="functions/use.html">use</a> <span class="w">warnings</span></code>
pragma (and the <b>-w</b> switch) produces some
lovely diagnostics.</p>
<p>See <a href="perldiag.html">perldiag</a> for explanations of all Perl's diagnostics. The <code class="inline"><a class="l_k" href="functions/use.html">use</a>
<span class="w">diagnostics</span></code>
pragma automatically turns Perl's normally terse warnings
and errors into these longer forms.</p>
<p>Compilation errors will tell you the line number of the error, with an
indication of the next token or token type that was to be examined.
(In a script passed to Perl via <b>-e</b> switches, each
<b>-e</b> is counted as one line.)</p>
<p>Setuid scripts have additional constraints that can produce error
messages such as "Insecure dependency". See <a href="perlsec.html">perlsec</a>.</p>
<p>Did we mention that you should definitely consider using the <b>-w</b>
switch?</p>
<a name="BUGS"></a><h1>BUGS</h1>
<p>The <b>-w</b> switch is not mandatory.</p>
<p>Perl is at the mercy of your machine's definitions of various
operations such as type casting, atof(), and floating-point
output with sprintf().</p>
<p>If your stdio requires a seek or eof between reads and writes on a
particular stream, so does Perl. (This doesn't apply to sysread()
and syswrite().)</p>
<p>While none of the built-in data types have any arbitrary size limits
(apart from memory size), there are still a few arbitrary limits: a
given variable name may not be longer than 251 characters. Line numbers
displayed by diagnostics are internally stored as short integers,
so they are limited to a maximum of 65535 (higher numbers usually being
affected by wraparound).</p>
<p>You may mail your bug reports (be sure to include full configuration
information as output by the myconfig program in the perl source
tree, or by <code class="inline"><span class="w">perl</span> -<span class="w">V</span></code>
) to perlbug@perl.org . If you've succeeded
in compiling perl, the <b>perlbug</b> script in the <i>utils/</i> subdirectory
can be used to help mail in a bug report.</p>
<p>Perl actually stands for Pathologically Eclectic Rubbish Lister, but
don't tell anyone I said that.</p>
<a name="NOTES"></a><h1>NOTES</h1>
<p>The Perl motto is "There's more than one way to do it." Divining
how many more is left as an exercise to the reader.</p>
<p>The three principal virtues of a programmer are Laziness,
Impatience, and Hubris. See the Camel Book for why.</p>
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