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2908 lines
110 KiB
2908 lines
110 KiB
<HTML>
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<HEAD>
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<TITLE>Rex Swain's HTMLified Perl 5 Reference Guide</TITLE>
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<META NAME="description" CONTENT="Perl 5 Reference Guide (in HTML)">
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<META NAME="keywords" CONTENT="perl, reference, summary">
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</HEAD>
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<BODY>
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<A NAME="top"></A>
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<CENTER>
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<H1>Rex Swain's HTMLified<BR>Perl 5 Reference Guide</H1>
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<P>Last updated 17 May 1997</P>
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<P>[ The <A HREF="http://www.pcnet.com/~rhswain/perl.html">original</A> ]
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[ <A HREF="http://www.man.ac.uk/~mbzalgd/perl/perl5-ref.html">.UK Mirror</A>
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via <A HREF="http://www.man.ac.uk/~mbzalgd">Alain Deckers</A> ]
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[ <A HREF="http://www.cs.uni-magdeburg.de/docs/perl5/index.html">.DE Mirror</A>
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via <A HREF="http://irb.cs.uni-magdeburg.de/~elkner">Jens Elkner</A> ]
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</P>
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</CENTER>
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<H4 ALIGN=center>Jump to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
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<CENTER>
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<TABLE BORDER=4 CELLPADDING=8><TR><TD>
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<CENTER>
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<H3><FONT COLOR="#FF0000">Please make a local copy of this HTML document!</FONT></H3>
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<P>Use your browser's <STRONG><U>F</U>ile, Save <U>A</U>s...</STRONG> command
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<BR>or I will get charged by my ISP for excessive bandwidth use.</P>
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Thank you!
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</CENTER>
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</TR></TD></TABLE>
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</CENTER>
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<P>This is an HTMLified version of the <I>Perl 5 Desktop Reference</I>,
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ISBN 1-56592-187-9, copyright © 1996 by
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<A HREF="http://www.xs4all.nl/~jvromans/">Johan Vromans</A>.
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HTML copyright © 1996-1997 by
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<A HREF="http://www.pcnet.com/~rhswain/">Rex Swain</A>.</P>
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<P>See <A HREF="http://www.pcnet.com/~rhswain/perl4.html">Rex Swain's HTMLified Perl 4 Reference Guide</A>
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for similar summary of Perl version 4.</P>
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<P>See <A HREF="http://www.ora.com/catalog/perlqr/">Perl 5 Desktop Reference</A>
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for information about ordering a printed copy ($6.95) of the booklet from O'Reilly.
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See <A HREF="http://www.xs4all.nl/~jvromans/perlref.html">The Perl Reference Guide</A>
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for pointers to a PostScript (free) version.</P>
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<P>If you want to learn Perl, see the book
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<A HREF="http://www.ora.com/catalog/lperl/">Learning Perl</A>
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by Randal L. Schwartz. If you want more detailed information about Perl, see the book
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<A HREF="http://www.ora.com/catalog/pperl/">Programming perl</A>
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by Larry Wall and Randal L. Schwartz.</P>
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<P>For more detail, see <A HREF="http://www.mit.edu/perl/perl.html">Perl Manual</A>
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or <A HREF="ftp://ftp.digital.com/pub/plan/perl/CPAN/doc/manual/html/perlfunc.html#perlfunc_alphabetical_0">Alphabetical Listing of Perl Functions</A>.
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<BR>For less detail, see <A HREF="http://www.perl.com/perl/">The Perl Language Home Page</A>.</P>
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<H4 ALIGN=center>Jump to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
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<!-- ----------------------------------------------------------------------------- -->
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<A NAME="contents"></A>
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<H2>Contents</H2>
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<TABLE>
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<TR><TD><UL>
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<LI><A HREF="#conventions">Conventions</A>
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</UL></TD></TR>
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<TR><TD><UL>
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<LI><A HREF="#options">Command-Line Options</A>
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<LI><A HREF="#literals">Literals</A>
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<LI><A HREF="#variables">Variables</A>
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<LI><A HREF="#operators">Operators</A>
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<LI><A HREF="#statements">Statements</A>
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<LI><A HREF="#subroutines">Subroutines, Packages and Modules</A>
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<LI><A HREF="#object">Object-Oriented Programming</A>
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<LI><A HREF="#arithmetic">Arithmetic Functions</A>
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<LI><A HREF="#conversion">Conversion Functions</A>
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<LI><A HREF="#structure">Structure Conversion</A>
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<LI><A HREF="#string">String Functions</A>
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<LI><A HREF="#array">Array and List Functions</A>
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<LI><A HREF="#regular">Regular Expressions</A>
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<LI><A HREF="#search">Search and Replace Functions</A>
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</UL></TD>
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<TD><UL>
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<LI><A HREF="#filetest">File Test Operators</A>
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<LI><A HREF="#fileoperations">File Operations</A>
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<LI><A HREF="#input">Input / Output</A>
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<LI><A HREF="#formats">Formats</A>
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<LI><A HREF="#directory">Directory Reading Routines</A>
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<LI><A HREF="#systeminteraction">System Interaction</A>
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<LI><A HREF="#networking">Networking</A>
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<LI><A HREF="#systemv">System V IPC</A>
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<LI><A HREF="#miscellaneous">Miscellaneous</A>
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<LI><A HREF="#information">Information from System Files</A>
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<LI><A HREF="#specialvariables">Special Variables</A>
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<LI><A HREF="#specialarrays">Special Arrays</A>
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<LI><A HREF="#environment">Environment Variables</A>
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<LI><A HREF="#debugger">The Perl Debugger</A>
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</UL></TD></TR>
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</TABLE>
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<H4 ALIGN=center>Jump to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
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<!-- ----------------------------------------------------------------------------- -->
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<A NAME="index"></A>
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<H2>Index</H2>
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<A HREF="#arithmetic">abs</A>
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<A HREF="#networking">accept</A>
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<A HREF="#systeminteraction">alarm</A>
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<A HREF="#operators">and</A>
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<A HREF="#specialarrays">ARGV</A>
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<A HREF="#arithmetic">ArithmeticFunctions</A>
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<A HREF="#array">ArrayListFunctions</A>
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<A HREF="#specialarrays">ArraysSpecial</A>
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<A HREF="#arithmetic">atan2</A>
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<A HREF="#subroutines">BEGIN</A>
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<A HREF="#networking">bind</A>
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<A HREF="#input">binmode</A>
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<A HREF="#subroutines">bless</A>
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<A HREF="#subroutines">caller</A>
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<A HREF="#systeminteraction">chdir</A>
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<A HREF="#fileoperations">chmod</A>
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<A HREF="#string">chomp</A>
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<A HREF="#string">chop</A>
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<A HREF="#conversion">chr</A>
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<A HREF="#systeminteraction">chroot</A>
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<A HREF="#input">close</A>
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<A HREF="#directory">closedir</A>
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<A HREF="#operators">cmp</A>
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<A HREF="#options">CommandLineOptions</A>
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<A HREF="#networking">connect</A>
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<A HREF="#contents">Contents</A>
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<A HREF="#statements">continue</A>
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<A HREF="#conventions">Conventions</A>
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<A HREF="#conversion">ConversionFunctions</A>
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<A HREF="#structure">ConversionStructure</A>
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<A HREF="#arithmetic">cos</A>
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<A HREF="#string">crypt</A>
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<A HREF="#input">dbmclose</A>
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<A HREF="#input">dbmopen</A>
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<A HREF="#debugger">Debugger</A>
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<A HREF="#miscellaneous">defined</A>
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<A HREF="#array">delete</A>
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<A HREF="#systeminteraction">die</A>
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<A HREF="#directory">DirectoryReadingRoutines</A>
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<A HREF="#statements">do</A>
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<A HREF="#subroutines">do</A>
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<A HREF="#miscellaneous">do</A>
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<A HREF="#miscellaneous">dump</A>
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<A HREF="#array">each</A>
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<A HREF="#statements">else</A>
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<A HREF="#statements">elsif</A>
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<A HREF="#subroutines">END</A>
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<A HREF="#specialarrays">ENV</A>
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<A HREF="#environment">EnvironmentVariables</A>
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<A HREF="#input">eof</A>
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<A HREF="#operators">eq</A>
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<A HREF="#string">eval</A>
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<A HREF="#miscellaneous">eval</A>
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<A HREF="#systeminteraction">exec</A>
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<A HREF="#array">exists</A>
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<A HREF="#systeminteraction">exit</A>
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<A HREF="#arithmetic">exp</A>
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<A HREF="#specialarrays">EXPORT</A>
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<A HREF="#specialarrays">EXPORT_OK</A>
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<A HREF="#regular">ExpressionsRegular</A>
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<A HREF="#input">fcntl</A>
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<A HREF="#input">fileno</A>
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<A HREF="#fileoperations">FileOperations</A>
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<A HREF="#information">FilesSystemInformationFrom</A>
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<A HREF="#filetest">FileTestOperators</A>
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<A HREF="#input">flock</A>
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<A HREF="#statements">for</A>
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<A HREF="#statements">foreach</A>
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<A HREF="#systeminteraction">fork</A>
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<A HREF="#formats">Formats</A>
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<A HREF="#formats">formline</A>
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<A HREF="#arithmetic">FunctionsArithmetic</A>
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<A HREF="#array">FunctionsArrayList</A>
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<A HREF="#conversion">FunctionsConversion</A>
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<A HREF="#search">FunctionsSearchReplace</A>
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<A HREF="#string">FunctionsString</A>
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<A HREF="#operators">ge</A>
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<A HREF="#input">getc</A>
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<A HREF="#systeminteraction">getlogin</A>
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<A HREF="#networking">getpeername</A>
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<A HREF="#systeminteraction">getpgrp</A>
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<A HREF="#systeminteraction">getppid</A>
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<A HREF="#systeminteraction">getpriority</A>
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<A HREF="#networking">getsockname</A>
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<A HREF="#networking">getsockopt</A>
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<A HREF="#systeminteraction">glob</A>
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<A HREF="#conversion">gmtime</A>
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<A HREF="#statements">goto</A>
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<A HREF="#subroutines">goto</A>
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<A HREF="#array">grep</A>
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<A HREF="#operators">gt</A>
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<A HREF="#conversion">hex</A>
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<A HREF="#environment">HOME</A>
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<A HREF="#statements">if</A>
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<A HREF="#subroutines">import</A>
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<A HREF="#specialarrays">INC</A>
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<A HREF="#index">Index</A>
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<A HREF="#string">index</A>
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<A HREF="#information">InformationFromSystemFiles</A>
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<A HREF="#input">InputOutput</A>
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<A HREF="#arithmetic">int</A>
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<A HREF="#systeminteraction">InteractionSystem</A>
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<A HREF="#input">ioctl</A>
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<A HREF="#specialarrays">ISA</A>
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<A HREF="#array">join</A>
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<A HREF="#array">keys</A>
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<A HREF="#systeminteraction">kill</A>
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<A HREF="#statements">last</A>
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<A HREF="#string">lc</A>
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<A HREF="#string">lcfirst</A>
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<A HREF="#operators">le</A>
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<A HREF="#string">length</A>
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<A HREF="#fileoperations">link</A>
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<A HREF="#array">ListArrayFunctions</A>
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<A HREF="#networking">listen</A>
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<A HREF="#literals">Literals</A>
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<A HREF="#miscellaneous">local</A>
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<A HREF="#conversion">localtime</A>
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<A HREF="#arithmetic">log</A>
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<A HREF="#environment">LOGDIR</A>
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<A HREF="#fileoperations">lstat</A>
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<A HREF="#operators">lt</A>
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<A HREF="#search">m</A>
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<A HREF="#array">map</A>
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<A HREF="#miscellaneous">Miscellaeous</A>
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<A HREF="#fileoperations">mkdir</A>
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<A HREF="#subroutines">Modules</A>
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<A HREF="#miscellaneous">my</A>
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<A HREF="#operators">ne</A>
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<A HREF="#networking">Networking</A>
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<A HREF="#statements">next</A>
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<A HREF="#subroutines">no</A>
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<A HREF="#operators">npt</A>
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<A HREF="#object">ObjectOrientedProgramming</A>
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<A HREF="#conversion">oct</A>
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<A HREF="#input">open</A>
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<A HREF="#directory">opendir</A>
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<A HREF="#fileoperations">OperationsFile</A>
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<A HREF="#operators">Operators</A>
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<A HREF="#filetest">OperatorsFileTest</A>
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<A HREF="#options">OptionsCommandLine</A>
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<A HREF="#operators">or</A>
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<A HREF="#conversion">ord</A>
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<A HREF="#input">OutputInput</A>
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<A HREF="#specialarrays">OVERLOAD</A>
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<A HREF="#structure">pack</A>
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<A HREF="#subroutines">package</A>
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<A HREF="#subroutines">Packages</A>
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<A HREF="#environment">PATH</A>
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<A HREF="#environment">PERL5DB</A>
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<A HREF="#environment">PERL5LIB</A>
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<A HREF="#environment">PERLLIB</A>
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<A HREF="#input">pipe</A>
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<A HREF="#array">pop</A>
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<A HREF="#search">pos</A>
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<A HREF="#input">print</A>
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<A HREF="#input">printf</A>
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<A HREF="#array">push</A>
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<A HREF="#string">quotemeta</A>
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<A HREF="#arithmetic">rand</A>
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<A HREF="#input">read</A>
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<A HREF="#directory">readdir</A>
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<A HREF="#directory">ReadingDirectoryRoutines</A>
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<A HREF="#fileoperations">readlink</A>
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<A HREF="#networking">recv</A>
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<A HREF="#statements">redo</A>
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<A HREF="#miscellaneous">ref</A>
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<A HREF="#regular">RegularExpressions</A>
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<A HREF="#fileoperations">rename</A>
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<A HREF="#search">ReplaceSearchFunctions</A>
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<A HREF="#subroutines">require</A>
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<A HREF="#miscellaneous">reset</A>
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<A HREF="#subroutines">return</A>
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<A HREF="#array">reverse</A>
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<A HREF="#directory">rewindir</A>
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<A HREF="#string">rindex</A>
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<A HREF="#fileoperations">rmdir</A>
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<A HREF="#directory">RoutinesDirectoryReading</A>
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<A HREF="#search">s</A>
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<A HREF="#array">scalar</A>
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<A HREF="#miscellaneous">scalar</A>
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<A HREF="#search">SearchReplaceFunctions</A>
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<A HREF="#input">seek</A>
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<A HREF="#directory">seekdir</A>
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<A HREF="#input">select</A>
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<A HREF="#networking">send</A>
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<A HREF="#systeminteraction">setpgrp</A>
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<A HREF="#systeminteraction">setpriority</A>
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<A HREF="#networking">setsockopt</A>
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<A HREF="#array">shift</A>
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<A HREF="#networking">shutdown</A>
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<A HREF="#specialarrays">SIG</A>
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<A HREF="#arithmetic">sin</A>
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<A HREF="#systeminteraction">sleep</A>
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<A HREF="#networking">socket</A>
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<A HREF="#networking">socketpair</A>
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<A HREF="#array">sort</A>
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<A HREF="#specialarrays">SpecialArrays</A>
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<A HREF="#specialvariables">SpecialVariables</A>
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<A HREF="#array">splice</A>
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<A HREF="#array">split</A>
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<A HREF="#input">sprintf</A>
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<A HREF="#arithmetic">sqrt</A>
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<A HREF="#arithmetic">srand</A>
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<A HREF="#fileoperations">stat</A>
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<A HREF="#statements">Statements</A>
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<A HREF="#string">StringFunctions</A>
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<A HREF="#structure">StructureConversion</A>
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<A HREF="#search">study</A>
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<A HREF="#subroutines">sub</A>
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<A HREF="#subroutines">Subroutines</A>
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<A HREF="#string">substr</A>
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<A HREF="#fileoperations">symlink</A>
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<A HREF="#systeminteraction">syscall</A>
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<A HREF="#input">sysread</A>
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<A HREF="#systeminteraction">system</A>
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<A HREF="#information">SystemFilesInformationFrom</A>
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<A HREF="#systeminteraction">SystemInteraction</A>
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<A HREF="#systemv">SystemVIPC</A>
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<A HREF="#input">syswrite</A>
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<A HREF="#input">tell</A>
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<A HREF="#directory">telldir</A>
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<A HREF="#filetest">TestFileOperators</A>
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<A HREF="#subroutines">tie</A>
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<A HREF="#arithmetic">time</A>
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<A HREF="#systeminteraction">times</A>
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<A HREF="#search">tr</A>
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<A HREF="#fileoperations">truncate</A>
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<A HREF="#string">uc</A>
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<A HREF="#string">ucfirst</A>
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<A HREF="#systeminteraction">umask</A>
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<A HREF="#miscellaneous">undef</A>
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<A HREF="#statements">unless</A>
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<A HREF="#fileoperations">unlink</A>
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<A HREF="#structure">unpack</A>
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<A HREF="#array">unshift</A>
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<A HREF="#subroutines">untie</A>
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<A HREF="#statements">until</A>
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<A HREF="#statements">until</A>
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<A HREF="#subroutines">use</A>
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<A HREF="#fileoperations">utime</A>
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<A HREF="#array">values</A>
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<A HREF="#variables">Variables</A>
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<A HREF="#environment">VariablesEnvironment</A>
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<A HREF="#specialvariables">VariablesSpecial</A>
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<A HREF="#conversion">vec</A>
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<A HREF="#systeminteraction">wait</A>
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<A HREF="#systeminteraction">waitpid</A>
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<A HREF="#miscellaneous">wantarray</A>
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<A HREF="#systeminteraction">warn</A>
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<A HREF="#statements">while</A>
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<A HREF="#formats">write</A>
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<A HREF="#operators">xor</A>
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<A HREF="#search">y</A>
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<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
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<!-- ----------------------------------------------------------------------------- -->
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<A NAME="conventions"></A>
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<H2>Conventions</H2>
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<TABLE CELLSPACING=0 CELLPADDING=0>
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<TR>
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<TD><TT><B>fixed </B></TT></TD>
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<TD>denotes literal text.</TD>
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</TR>
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<TR>
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<TD><FONT SIZE="-1">THIS</FONT></TD>
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<TD>means variable text, i.e., things you must fill in.</TD>
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</TR>
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<TR>
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<TD><FONT SIZE="-1">THIS†</FONT></TD>
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<TD>means that <FONT SIZE="-1">THIS</FONT> will default to <TT><B>$_</B></TT> if omitted.</TD>
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</TR>
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<TR>
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<TD><B>word</B></TD>
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<TD>is a keyword, i.e., a word with a special meaning.</TD>
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</TR>
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<TR>
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<TD><FONT SIZE="-1">RETURN key </FONT></TD>
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<TD>denotes pressing a keyboard key.</TD>
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</TR>
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<TR>
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<TD>[...]</TD>
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<TD>denotes an optional part.</TD>
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</TR>
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</TABLE>
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<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
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<!-- ----------------------------------------------------------------------------- -->
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|
|
<A NAME="options"></A>
|
|
<H2>Command-Line Options</H2>
|
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|
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<DL COMPACT>
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<DT><TT><B>-a</B></TT>
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<DD>turns on autosplit mode when used with <TT><B>-n</B></TT> or <TT><B>-p</B></TT>.
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Splits to <TT><B>@F</B></TT>.
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<DT><TT><B>-c</B></TT>
|
|
<DD>checks syntax but does not execute.
|
|
|
|
<DT><TT><B>-d</B></TT>
|
|
<DD>runs the script under the debugger.
|
|
Use <TT><B>-de 0</B></TT> to start the debugger without a script
|
|
|
|
<DT><TT><B>-D</B></TT> <FONT SIZE="-1">NUMBER</FONT>
|
|
<DD>sets debugging flags.
|
|
|
|
<DT><TT><B>-e</B></TT> <FONT SIZE="-1">COMMANDLINE</FONT>
|
|
<DD>may be used to enter a single line of script.
|
|
Multiple <TT><B>-e</B></TT> commands may be given to build up a multiline script.
|
|
|
|
<DT><TT><B>-F</B></TT> <FONT SIZE="-1">REGEXP</FONT>
|
|
<DD>specifies a regular expression to split on
|
|
if <TT><B>-a</B></TT> is in effect.
|
|
|
|
<DT><TT><B>-i</B></TT><FONT SIZE="-1">EXT</FONT>
|
|
<DD>files processed by the <TT><B>< ></B></TT> construct are
|
|
to be edited in place.
|
|
|
|
<DT><TT><B>-I</B></TT><FONT SIZE="-1">DIR</FONT>
|
|
<DD>with <TT><B>-P</B></TT>, tells the C preprocessor where to look for include files.
|
|
The directory is prepended to <TT><B>@INC</B></TT>.
|
|
|
|
<DT><TT><B>-l</B></TT> [<FONT SIZE="-1">OCTNUM</FONT>]
|
|
<DD>enables automatic line-end processing, e.g., <TT><B>-l013</B></TT>.
|
|
|
|
<DT><TT><B>-n</B></TT>
|
|
<DD>assumes an input loop around your script. Lines are not printed.
|
|
|
|
<DT><TT><B>-p</B></TT>
|
|
<DD>assumes an input loop around your script. Lines are printed.
|
|
|
|
<DT><TT><B>-P</B></TT>
|
|
<DD>runs the C preprocessor on the script before compilation by Perl.
|
|
|
|
<DT><TT><B>-s</B></TT>
|
|
<DD>interprets <TT><B>-xxx</B></TT> on the command line as a switch and sets
|
|
the corresponding variable <TT><B>$xxx</B></TT> in the script.
|
|
|
|
<DT><TT><B>-S</B></TT>
|
|
<DD>uses the <TT><B>PATH</B></TT> environment variable to search for the script.
|
|
|
|
<DT><TT><B>-T</B></TT>
|
|
<DD>forces taint checking.
|
|
|
|
<DT><TT><B>-u</B></TT>
|
|
<DD>dumps core after compiling the script. To be used with the <I>undump</I>(1)
|
|
program (where available).
|
|
|
|
<DT><TT><B>-U</B></TT>
|
|
<DD>allows perl to perform unsafe operations.
|
|
|
|
<DT><TT><B>-v</B></TT>
|
|
<DD>prints the version and patchlevel of your Perl executable.
|
|
|
|
<DT><TT><B>-w</B></TT>
|
|
<DD>prints warnings about possible spelling errors and other error-prone
|
|
constructs in the script.
|
|
|
|
<DT><TT><B>-x</B></TT> [<FONT SIZE="-1">DIR</FONT>]
|
|
<DD>extracts Perl program from input stream.
|
|
If <FONT SIZE="-1">DIR</FONT> is specified,
|
|
switches to this directory before running the program.
|
|
|
|
<DT><TT><B>-0</B></TT><FONT SIZE="-1">VAL</FONT>
|
|
<DD>(that's the number zero.) Designates an initial value for the record
|
|
separator <TT><B>$/</B></TT>. See also <TT><B>-l</B></TT>
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="literals"></A>
|
|
<H2>Literals</H2>
|
|
|
|
<DL>
|
|
|
|
<DT>Numeric:
|
|
<DD><TT><B>123</B></TT>
|
|
<DD><TT><B>1_234</B></TT>
|
|
<DD><TT><B>123.4</B></TT>
|
|
<DD><TT><B>5E-10</B></TT>
|
|
<DD><TT><B>0xff</B></TT> (hex)
|
|
<DD><TT><B>0377</B></TT> (octal)
|
|
|
|
<DT>String:
|
|
<DL>
|
|
|
|
<DT><TT><B>'abc'</B></TT>
|
|
<DD>literal string, no variable interpolation or escape characters,
|
|
except <TT><B>\'</B></TT> and <TT><B>\\</B></TT>.
|
|
Also: <TT><B>q/abc/</B></TT>.
|
|
Almost any pair of delimiters can be used instead of <TT><B>/</B></TT>...<TT><B>/</B></TT>.
|
|
|
|
<DT><TT><B>"abc"</B></TT>
|
|
<DD>Variables are interpolated and escape sequences are processed.
|
|
Also: <TT><B>qq/abc/</B></TT>.
|
|
<BR>Escape sequences:
|
|
<TT><B>\t</B></TT> (Tab),
|
|
<TT><B>\n</B></TT> (Newline),
|
|
<TT><B>\r</B></TT> (Return),
|
|
<TT><B>\f</B></TT> (Formfeed),
|
|
<TT><B>\b</B></TT> (Backspace),
|
|
<TT><B>\a</B></TT> (Alarm),
|
|
<TT><B>\e</B></TT> (Escape),
|
|
<TT><B>\033</B></TT> (octal),
|
|
<TT><B>\x1b</B></TT> (hex),
|
|
<TT><B>\c[</B></TT> (control)
|
|
<BR><TT><B>\l</B></TT> and <TT><B>\u</B></TT> lowercase/uppercase the following character.
|
|
<TT><B>\L</B></TT> and <TT><B>\U</B></TT> lowercase/uppercase until a <TT><B>\E</B></TT>
|
|
is encountered.
|
|
<TT><B>\Q</B></TT> quote regular expression characters until a <TT><B>\E</B></TT>
|
|
is encountered.
|
|
|
|
<DT><TT><B>`</B></TT><FONT SIZE="-1">COMMAND</FONT><TT><B>`</B></TT>
|
|
<DD>evaluates to the output of the <FONT SIZE="-1">COMMAND</FONT>.
|
|
Also: <TT><B>qx/</B></TT><FONT SIZE="-1">COMMAND</FONT><TT><B>/</B></TT>.
|
|
</DL>
|
|
|
|
<DT>Array:
|
|
<DD><TT><B>(1, 2, 3)</B></TT>. <TT><B>()</B></TT> is an empty array.
|
|
<BR><TT><B>(1..4)</B></TT> is the same as <TT><B>(1,2,3,4)</B></TT>,
|
|
<BR>likewise <TT><B>('a'..'z')</B></TT>.
|
|
<BR><TT><B>qw/foo bar </B></TT>...<TT><B>/</B></TT> is the same as <TT><B>('foo','bar',</B></TT>...<TT><B>)</B></TT>.
|
|
|
|
<DT>Array reference:
|
|
<DD><TT><B>[1,2,3]</B></TT>
|
|
|
|
<DT>Hash (associative array):
|
|
<DD><TT><B>(</B></TT><FONT SIZE="-1">KEY1</FONT><TT><B>,</B></TT>
|
|
<FONT SIZE="-1">VAL1</FONT><TT><B>,</B></TT>
|
|
<FONT SIZE="-1">KEY2</FONT><TT><B>,</B></TT>
|
|
<FONT SIZE="-1">VAL2</FONT><TT><B>,</B></TT>...<TT><B>)</B></TT>
|
|
<BR>Also
|
|
<TT><B>(</B></TT><FONT SIZE="-1">KEY1</FONT><TT><B>=></B></TT>
|
|
<FONT SIZE="-1">VAL1</FONT><TT><B>,</B></TT>
|
|
<FONT SIZE="-1">KEY2</FONT><TT><B>=></B></TT>
|
|
<FONT SIZE="-1">VAL2</FONT><TT><B>,</B></TT>...<TT><B>)</B></TT>
|
|
|
|
<DT>Hash reference:
|
|
<DD><TT><B>{</B></TT><FONT SIZE="-1">KEY1</FONT><TT><B>,</B></TT>
|
|
<FONT SIZE="-1">VAL1</FONT><TT><B>,</B></TT>
|
|
<FONT SIZE="-1">KEY2</FONT><TT><B>,</B></TT>
|
|
<FONT SIZE="-1">VAL2</FONT><TT><B>,</B></TT>...<TT><B>}</B></TT>
|
|
|
|
<DT>Code reference:
|
|
<DD><B>sub</B> <TT><B>{</B></TT><FONT SIZE="-1">STATEMENTS</FONT><TT><B>}</B></TT>
|
|
|
|
<DT>Filehandles:
|
|
<DD>
|
|
<TT><B><STDIN></B></TT>,
|
|
<TT><B><STDOUT></B></TT>,
|
|
<TT><B><STDERR></B></TT>,
|
|
<TT><B><ARGV></B></TT>,
|
|
<TT><B><DATA></B></TT>.
|
|
<BR>User-specified:
|
|
<FONT SIZE="-1">HANDLE</FONT>,
|
|
<TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT>.
|
|
|
|
<DT>Globs:
|
|
<DD><TT><B><</B></TT><FONT SIZE="-1">PATTERN</FONT><TT><B>></B></TT>
|
|
evaluates to all filenames according to the pattern.
|
|
Use <TT><B><${</B></TT><FONT SIZE="-1">VAR</FONT><TT><B>}></B></TT>
|
|
or <B>glob</B> <TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT>
|
|
to glob from a variable.
|
|
|
|
<DT>Here-Is:
|
|
<DD><TT><B><<</B></TT><FONT SIZE="-1">IDENTIFIER</FONT>
|
|
<BR>Shell-style "here document."
|
|
|
|
<DT>Special tokens:
|
|
<DD><TT><B>__FILE__</B></TT>: filename;
|
|
<TT><B>__LINE__</B></TT>: line number;
|
|
<TT><B>__END__</B></TT>: end of program;
|
|
remaining lines can be read using the filehandle <TT><B>DATA</B></TT>.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="variables"></A>
|
|
<H2>Variables</H2>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$var</B></TT></TD>
|
|
<TD VALIGN=top>a simple scalar variable.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$var[28]</B></TT></TD>
|
|
<TD VALIGN=top>29th element of array <TT><B>@var</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$p = \@var</B></TT></TD>
|
|
<TD VALIGN=top>now <TT><B>$p</B></TT> is a reference to array <TT><B>@var</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$$p[28]</B></TT></TD>
|
|
<TD VALIGN=top>29th element of array referenced by <TT><B>$p</B></TT>.
|
|
<BR>Also, <TT><B>$p->[28]</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$var[-1]</B></TT></TD>
|
|
<TD VALIGN=top>last element of array <TT><B>@var</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$var[$i][$j]</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>$j</B></TT>th element of the <TT><B>$i</B></TT>th element of
|
|
array <TT><B>@var</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$var{'Feb'}</B></TT></TD>
|
|
<TD VALIGN=top>one value from hash (associative array) <TT><B>%var</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$p = \%var</B></TT></TD>
|
|
<TD VALIGN=top>now <TT><B>$p</B></TT> is a reference to hash <TT><B>%var</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$$p{'Feb'}</B></TT></TD>
|
|
<TD VALIGN=top>a value from hash referenced by <TT><B>$p</B></TT>.
|
|
<BR>Also, <TT><B>$p->{'Feb'}</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$#var</B></TT></TD>
|
|
<TD VALIGN=top>last index of array <TT><B>@var</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>@var</B></TT></TD>
|
|
<TD VALIGN=top>the entire array;
|
|
in a scalar context, the number of elements in the array.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>@var[3,4,5]</B></TT></TD>
|
|
<TD VALIGN=top>a slice of array <TT><B>@var</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>@var{'a','b'}</B></TT></TD>
|
|
<TD VALIGN=top>a slice of <TT><B>%var</B></TT>;
|
|
same as <TT><B>($var{'a'},$var{'b'})</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>%var</B></TT></TD>
|
|
<TD VALIGN=top>the entire hash;
|
|
in a scalar context, <B>true</B> if the hash has elements.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>$var{'a',1,</B></TT>...<TT><B>}</B></TT></TD>
|
|
<TD VALIGN=top>emulates a multidimensional array.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>('a'</B></TT>...<TT><B>'z')[4,7,9]</B></TT></TD>
|
|
<TD VALIGN=top>a slice of an array literal.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><FONT SIZE="-1">PKG</FONT><TT><B>::</B></TT><FONT SIZE="-1">VAR</FONT></TD>
|
|
<TD VALIGN=top>a variable from a package, e.g.,
|
|
<TT><B>$pkg::var</B></TT>, <TT><B>@pkg::ary</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>\</B></TT><FONT SIZE="-1">OBJECT</FONT></TD>
|
|
<TD VALIGN=top>reference to an object, e.g.,
|
|
<TT><B>\$var</B></TT>, <TT><B>\%hash</B></TT>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>*</B></TT><FONT SIZE="-1">NAME</FONT></TD>
|
|
<TD VALIGN=top>refers to all objects represented by <FONT SIZE="-1">NAME</FONT>.
|
|
<BR><TT><B>*n1 = *n2</B></TT> makes <TT><B>n1</B></TT> an alias for <TT><B>n2</B></TT>.
|
|
<BR><TT><B>*n1 = $n2</B></TT> makes <TT><B>$n1</B></TT> an alias for <TT><B>$n2</B></TT>.
|
|
</TD>
|
|
</TR>
|
|
|
|
</TABLE>
|
|
|
|
<P>
|
|
You can always use a <TT><B>{</B></TT><FONT SIZE="-1">BLOCK</FONT><TT><B>}</B></TT>
|
|
returning the right type of reference instead of the variable identifier, e.g.,
|
|
<TT><B>${</B></TT>...<TT><B>}</B></TT>,
|
|
<TT><B>&{</B></TT>...<TT><B>}</B></TT>.
|
|
<TT><B>$$p</B></TT> is just a shorthand for <TT><B>${$p}</B></TT>.
|
|
</P>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<A NAME="operators"></A>
|
|
<H2>Operators</H2>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>**</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Exponentiation</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD NOWRAP VALIGN=top><TT><B>+ - </B></TT></TD>
|
|
<TD NOWRAP VALIGN=top><TT><B>* / </B></TT></TD>
|
|
<TD>Addition, subtraction, multiplication, division</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>%</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Modulo division</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>& |</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>^</B></TT></TD>
|
|
<TD>Bitwise AND, bitwise OR, bitwise exclusive OR</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>>></B></TT></TD>
|
|
<TD VALIGN=top><TT><B><<</B></TT></TD>
|
|
<TD>Bitwise shift right, bitwise shift left</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>||</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>&&</B></TT></TD>
|
|
<TD>Logical OR, logical AND</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>.</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Concatenation of two strings</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>x</B></TT></TD>
|
|
<TD VALIGN=top></TD>
|
|
<TD VALIGN=top>Returns a string or array consisting of the left operand (an array or a string)
|
|
repeated the number of times specified by the right operand</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=3>
|
|
All of the above operators also have an assignment operator,
|
|
e.g., <TT><B>.=</B></TT></TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>-></B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Dereference operator</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>\</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Reference (unary)</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>!</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>~</B></TT></TD>
|
|
<TD>Negation (unary), bitwise complement (unary)</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>++</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>--</B></TT></TD>
|
|
<TD>Auto-increment (magical on strings), auto-decrement</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>==</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>!=</B></TT></TD>
|
|
<TD>Numeric equality, inequality</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>eq</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>ne</B></TT></TD>
|
|
<TD>String equality, inequality</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B><</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>></B></TT></TD>
|
|
<TD>Numeric less than, greater than</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>lt</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>gt</B></TT></TD>
|
|
<TD>String less than, greater than</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B><=</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>>=</B></TT></TD>
|
|
<TD>Numeric less (greater) than or equal to</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>le</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>ge</B></TT></TD>
|
|
<TD>String less (greater) than or equal to</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B><=></B></TT></TD>
|
|
<TD VALIGN=top><TT><B>cmp</B></TT></TD>
|
|
<TD>Numeric (string) compare. Returns -1, 0, 1.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>=~</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>!~</B></TT></TD>
|
|
<TD>Search pattern, substitution, or translation (negated)</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>..</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Range (scalar context) or enumeration (array context)</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>?:</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Alternation (if-then-else) operator</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>,</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Comma operator, also list element separator.
|
|
You can also use <TT><B>=></B></TT>.
|
|
</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>not</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Low-precedence negation
|
|
</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>and</B></TT></TD>
|
|
<TD></TD>
|
|
<TD>Low-precedence AND
|
|
</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD VALIGN=top><TT><B>or</B></TT></TD>
|
|
<TD VALIGN=top><TT><B>xor</B></TT></TD>
|
|
<TD>Low-precedence OR, exclusive OR
|
|
</TD>
|
|
</TR>
|
|
|
|
</TABLE>
|
|
|
|
<P>All Perl functions can be used as list operators, in which case
|
|
they have very high or very low precedence, depending on
|
|
whether you look at the left or the right side of the operator.
|
|
Only the operators <B>not</B>, <B>and</B>, <B>or</B> and <B>xor</B> have lower precedence.</P>
|
|
|
|
<P>A "list" is a list of expressions, variables, or lists. An array
|
|
variable or an array slice may always be used instead of a list.</P>
|
|
|
|
<P>Parentheses can be added around the parameter lists
|
|
to avoid precedence problems.</P>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="statements"></A>
|
|
<H2>Statements</H2>
|
|
|
|
<P>Every statement is an expression, optionally followed by a modifier,
|
|
and terminated by a semicolon. The semicolon may be omitted if the
|
|
statement is the final one in a <FONT SIZE="-1">BLOCK</FONT>.</P>
|
|
|
|
<P>Execution of expressions can depend on other expressions using one of the modifiers
|
|
<B>if</B>, <B>unless</B>, <B>while</B> or <B>until</B>, for example:</P>
|
|
|
|
<UL>
|
|
<FONT SIZE="-1">EXPR1</FONT> <B>if</B> <FONT SIZE="-1">EXPR2</FONT> <TT><B>;</B></TT>
|
|
<BR>
|
|
<FONT SIZE="-1">EXPR1</FONT> <B>until</B> <FONT SIZE="-1">EXPR2</FONT> <TT><B>;</B></TT>
|
|
</UL>
|
|
|
|
<P>The logical operators <TT><B>||</B></TT>,
|
|
<TT><B>&&</B></TT> or
|
|
<TT><B>?:</B></TT> also allow conditional execution:</P>
|
|
|
|
<UL>
|
|
<FONT SIZE="-1">EXPR1</FONT> <TT><B>||</B></TT> <FONT SIZE="-1">EXPR2</FONT> <TT><B>;</B></TT>
|
|
<BR>
|
|
<FONT SIZE="-1">EXPR1</FONT> <TT><B>?</B></TT> <FONT SIZE="-1">EXPR2</FONT> <TT><B>:</B></TT> <FONT SIZE="-1">EXPR3</FONT> <TT><B>;</B></TT>
|
|
</UL>
|
|
|
|
<P>Statements can be combined to form a <FONT SIZE="-1">BLOCK</FONT>
|
|
when enclosed in <TT><B>{}</B></TT>. Blocks may be used to control flow:</P>
|
|
|
|
<UL>
|
|
<B>if</B> <TT><B>(</B></TT><FONT SIZE="-1">EXPR</FONT><TT><B>)</B></TT> <FONT SIZE="-1">BLOCK</FONT>
|
|
[ [ <B>elsif</B> <TT><B>(</B></TT><FONT SIZE="-1">EXPR</FONT><TT><B>)</B></TT> <FONT SIZE="-1">BLOCK</FONT> ... ]
|
|
<B>else</B> <FONT SIZE="-1">BLOCK</FONT> ]
|
|
<BR>
|
|
<B>unless</B> <TT><B>(</B></TT><FONT SIZE="-1">EXPR</FONT><TT><B>)</B></TT> <FONT SIZE="-1">BLOCK</FONT>
|
|
[ <B>else</B> <FONT SIZE="-1">BLOCK</FONT> ]
|
|
<BR>
|
|
[ <FONT SIZE="-1">LABEL</FONT><TT><B>:</B></TT> ]
|
|
<B>while</B> (<FONT SIZE="-1">EXPR</FONT>) <FONT SIZE="-1">BLOCK</FONT> [ <B>continue</B> <FONT SIZE="-1">BLOCK</FONT> ]
|
|
<BR>
|
|
[ <FONT SIZE="-1">LABEL</FONT><TT><B>:</B></TT> ]
|
|
<B>until</B> (<FONT SIZE="-1">EXPR</FONT>) <FONT SIZE="-1">BLOCK</FONT> [ <B>continue</B> <FONT SIZE="-1">BLOCK</FONT> ]
|
|
<BR>
|
|
[ <FONT SIZE="-1">LABEL</FONT><TT><B>:</B></TT> ]
|
|
<B>for</B> (<FONT SIZE="-1">EXPR</FONT><TT><B>;</B></TT> <FONT SIZE="-1">EXPR</FONT><TT><B>;</B></TT> <FONT SIZE="-1">EXPR</FONT>) <FONT SIZE="-1">BLOCK</FONT>
|
|
<BR>
|
|
[ <FONT SIZE="-1">LABEL</FONT><TT><B>:</B></TT> ]
|
|
<B>foreach</B> <FONT SIZE="-1">VAR†</FONT> (<FONT SIZE="-1">LIST</FONT>) <FONT SIZE="-1">BLOCK</FONT>
|
|
<BR>
|
|
[ <FONT SIZE="-1">LABEL</FONT><TT><B>:</B></TT> ]
|
|
<FONT SIZE="-1">BLOCK</FONT> [ <B>continue</B> <FONT SIZE="-1">BLOCK</FONT> ]
|
|
</UL>
|
|
|
|
<P>Program flow can be controlled with:</P>
|
|
|
|
<UL>
|
|
<TABLE CELLPADDING=0 CELLSPACING=0>
|
|
<TR><TD NOWRAP VALIGN=top><B>goto</B> <FONT SIZE="-1">LABEL</FONT></TD>
|
|
<TD>Continue execution at the specified label.</TD></TR>
|
|
<TR><TD NOWRAP VALIGN=top><B>last</B> [ <FONT SIZE="-1">LABEL</FONT> ]</TD>
|
|
<TD>Immediately exits the loop in question. Skips continue block.</TD></TR>
|
|
<TR><TD NOWRAP VALIGN=top><B>next</B> [ <FONT SIZE="-1">LABEL</FONT> ]</TD>
|
|
<TD>Starts the next iteration of the loop.</TD></TR>
|
|
<TR><TD NOWRAP VALIGN=top><B>redo</B> [ <FONT SIZE="-1">LABEL</FONT> ] </TD>
|
|
<TD>Restarts the loop block without evaluating the conditional again.</TD></TR>
|
|
</TABLE>
|
|
</UL>
|
|
|
|
<P>Special forms are:</P>
|
|
|
|
<UL>
|
|
<B>do</B> <FONT SIZE="-1">BLOCK</FONT> <B>while</B> <FONT SIZE="-1">EXPR</FONT> <TT><B>;</B></TT>
|
|
<BR>
|
|
<B>do</B> <FONT SIZE="-1">BLOCK</FONT> <B>until</B> <FONT SIZE="-1">EXPR</FONT> <TT><B>;</B></TT>
|
|
</UL>
|
|
|
|
<P>which are guaranteed to perform <FONT SIZE="-1">BLOCK</FONT>
|
|
once before testing <FONT SIZE="-1">EXPR</FONT>, and</P>
|
|
|
|
<UL>
|
|
<B>do</B> <FONT SIZE="-1">BLOCK</FONT>
|
|
</UL>
|
|
|
|
<P>which effectively turns <FONT SIZE="-1">BLOCK</FONT> into an expression.</P>
|
|
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="subroutines"></A>
|
|
<H2>Subroutines, Packages and Modules</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><TT><B>&</B></TT><FONT SIZE="-1">SUBROUTINE LIST</FONT>
|
|
<DD>Executes a <FONT SIZE="-1">SUBROUTINE</FONT> declared by a <B>sub</B> declaration, and
|
|
returns the value of the last expression evaluated in <FONT SIZE="-1">SUBROUTINE</FONT>.
|
|
<FONT SIZE="-1">SUBROUTINE</FONT> can be an expression yielding a reference to a code object.
|
|
The <TT><B>&</B></TT> may be omitted if the subroutine has been declared
|
|
before being used.
|
|
|
|
<DT><B>bless</B> <FONT SIZE="-1">REF</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">PACKAGE</FONT> ]
|
|
<DD>Turns the object <FONT SIZE="-1">REF</FONT>
|
|
into an object in <FONT SIZE="-1">PACKAGE</FONT>.
|
|
Returns the reference.
|
|
|
|
<DT><B>caller</B> [ <FONT SIZE="-1">EXPR</FONT> ]
|
|
<DD>Returns an array (<TT><B>$</B></TT>package,<TT><B>$</B></TT>file,<TT><B>$</B></TT>line,...)
|
|
for a specific subroutine call.
|
|
<TT><B>caller</B></TT> returns this info for the current subroutine,
|
|
<TT><B>caller(1)</B></TT> for the caller of this subroutine, etc.
|
|
Returns <B>false</B> if no caller.
|
|
|
|
<DT><B>do</B> <FONT SIZE="-1">SUBROUTINE</FONT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Depreciated form of <TT><B>&</B></TT><FONT SIZE="-1">SUBROUTINE</FONT>.
|
|
|
|
<DT><B>goto</B> <TT><B>&</B></TT><FONT SIZE="-1">SUBROUTINE</FONT>
|
|
<DD>Substitutes a call to <FONT SIZE="-1">SUBROUTINE</FONT> for the current subroutine.
|
|
|
|
<DT><B>import</B> <FONT SIZE="-1">MODULE</FONT> [ [ <FONT SIZE="-1">VERSION</FONT> ] <FONT SIZE="-1">LIST</FONT> ]
|
|
<DD>Imports the named subroutines from <FONT SIZE="-1">MODULE</FONT>.
|
|
|
|
<DT><B>no</B> <FONT SIZE="-1">MODULE</FONT> [ <FONT SIZE="-1">LIST</FONT> ]
|
|
<DD>Cancels imported semantics. See <B>use</B>.
|
|
|
|
<DT><B>package</B> <FONT SIZE="-1">NAME</FONT>
|
|
<DD>Designates the remainder of the current block as a package.
|
|
|
|
<DT><B>require</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>If <FONT SIZE="-1">EXPR</FONT> is numeric, requires Perl to be at least that
|
|
version. Otherwise <FONT SIZE="-1">EXPR</FONT> must be the name of a file
|
|
that is included from the Perl library. Does not
|
|
include more than once, and yields a fatal error if
|
|
the file does not evaluate to a <B>true</B> value.
|
|
If <FONT SIZE="-1">EXPR</FONT> is a bare word, assumes extension <TT><B>.pm</B></TT>
|
|
for the name of the file.
|
|
|
|
<DT><B>return</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Returns from a subroutine with the value specified.
|
|
|
|
<DT><B>sub</B> <FONT SIZE="-1">NAME</FONT> <TT><B>{</B></TT> <FONT SIZE="-1">EXPR</FONT> <TT><B>;</B></TT> ... <TT><B>}</B></TT>
|
|
<DD>Designates <FONT SIZE="-1">NAME</FONT> as a subroutine.
|
|
Parameters are passed by reference as array <TT><B>@_</B></TT>.
|
|
Returns the value of the last expression evaluated.
|
|
|
|
<DT>[ <B>sub</B> ] <TT><B>BEGIN</B></TT> <TT><B>{</B></TT> <FONT SIZE="-1">EXPR</FONT> <TT><B>;</B></TT> ... <TT><B>}</B></TT>
|
|
<DD>Defines a setup <FONT SIZE="-1">BLOCK</FONT> to be called before execution.
|
|
|
|
<DT>[ <B>sub</B> ] <TT><B>END</B></TT> <TT><B>{</B></TT> <FONT SIZE="-1">EXPR</FONT> <TT><B>;</B></TT> ... <TT><B>}</B></TT>
|
|
<DD>Defines a cleanup <FONT SIZE="-1">BLOCK</FONT> to be called upon termination.
|
|
|
|
<DT><B>tie</B> <FONT SIZE="-1">VAR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">PACKAGE</FONT><TT><B>,</B></TT> [ <FONT SIZE="-1">LIST</FONT> ]
|
|
<DD>Ties a variable to a package that will handle it.
|
|
Can be used to bind a dbm or ndbm file to a hash.
|
|
|
|
<DT><B>untie</B> <FONT SIZE="-1">VAR</FONT>
|
|
<DD>Breaks the binding between the variable and the package.
|
|
|
|
<DT><B>use</B> <FONT SIZE="-1">MODULE</FONT> [ [ <FONT SIZE="-1">VERSION</FONT> ] <FONT SIZE="-1">LIST</FONT> ]
|
|
<DD>Imports semantics from the named module into the current package.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="object"></A>
|
|
<H2>Object-Oriented Programming</H2>
|
|
|
|
<P>Perl rules of object oriented programming:</P>
|
|
|
|
<UL>
|
|
<LI>An object is simply a reference that happens to know which class it
|
|
belongs to. Objects are blessed, references are not.
|
|
<LI>A class is simply a package that happens to provide methods to deal
|
|
with object references. If a package fails to provide a method, the base classes as
|
|
listed in <TT><B>@ISA</B></TT> are searched.
|
|
<LI>A method is simply a subroutine that expects an object reference (or a
|
|
package name, for static methods) as the first argument.
|
|
</UL>
|
|
|
|
<P>Methods can be applied with:</P>
|
|
|
|
<UL>
|
|
<FONT SIZE="-1">METHOD</FONT> <FONT SIZE="-1">OBJREF</FONT> <FONT SIZE="-1">PARAMETERS</FONT>
|
|
or<BR>
|
|
<FONT SIZE="-1">OBJREF</FONT><TT><B>-></B></TT><FONT SIZE="-1">METHOD</FONT> <FONT SIZE="-1">PARAMETERS</FONT>
|
|
</UL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="arithmetic"></A>
|
|
<H2>Arithmetic Functions</H2>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR><TD VALIGN=top><B>abs</B> <FONT SIZE="-1">EXPR†</FONT></TD>
|
|
<TD VALIGN=top>Returns the absolute value of its operand.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>atan2</B> <FONT SIZE="-1">Y</FONT><TT><B>,</B></TT><FONT SIZE="-1">X</FONT></TD>
|
|
<TD VALIGN=top>Returns the arctangent of <FONT SIZE="-1">Y/X</FONT> in the range -pi to pi.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>cos</B> <FONT SIZE="-1">EXPR†</FONT></TD>
|
|
<TD VALIGN=top>Returns the cosine of <FONT SIZE="-1">EXPR</FONT> (expressed in radians).</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>exp</B> <FONT SIZE="-1">EXPR†</FONT></TD>
|
|
<TD VALIGN=top>Returns <TT><B>e</B></TT> to the power of <FONT SIZE="-1">EXPR</FONT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>int</B> <FONT SIZE="-1">EXPR†</FONT></TD>
|
|
<TD VALIGN=top>Returns the integer portion of <FONT SIZE="-1">EXPR</FONT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>log</B> <FONT SIZE="-1">EXPR†</FONT></TD>
|
|
<TD VALIGN=top>Returns natural logarithm (base <TT><B>e</B></TT>) of <FONT SIZE="-1">EXPR</FONT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>rand</B> [ <FONT SIZE="-1">EXPR</FONT> ]</TD>
|
|
<TD VALIGN=top>Returns a random fractional number between 0 and the value of <FONT SIZE="-1">EXPR</FONT>.
|
|
If <FONT SIZE="-1">EXPR</FONT> is omitted, returns a value between 0 and 1.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>sin</B> <FONT SIZE="-1">EXPR†</FONT></TD>
|
|
<TD VALIGN=top>Returns the sine of <FONT SIZE="-1">EXPR</FONT> (expressed in radians).</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>sqrt</B> <FONT SIZE="-1">EXPR†</FONT></TD>
|
|
<TD VALIGN=top>Returns the square root of <FONT SIZE="-1">EXPR</FONT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top NOWRAP><B>srand</B> [ <FONT SIZE="-1">EXPR</FONT> ] </TD>
|
|
<TD VALIGN=top>Sets the random number seed for the <B>rand</B> operator.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><B>time</B></TD>
|
|
<TD VALIGN=top>Returns the number of seconds since January 1, 1970. Suitable for
|
|
feeding to <B>gmtime</B> and <B>localtime</B>.</TD></TR>
|
|
|
|
</TABLE>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="conversion"></A>
|
|
<H2>Conversion Functions</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>chr</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Returns the character represented by the decimal value <FONT SIZE="-1">EXPR</FONT>.
|
|
|
|
<DT><B>gmtime</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Converts a time as returned by the <B>time</B> function to a 9-element array
|
|
(0: <TT><B>$</B></TT>sec,
|
|
1: <TT><B>$</B></TT>min,
|
|
2: <TT><B>$</B></TT>hour,
|
|
3: <TT><B>$</B></TT>mday,
|
|
4: <TT><B>$</B></TT>mon,
|
|
5: <TT><B>$</B></TT>year,
|
|
6: <TT><B>$</B></TT>wday,
|
|
7: <TT><B>$</B></TT>yday,
|
|
8: <TT><B>$</B></TT>isdst)
|
|
with the time analyzed for the Greenwich time zone. <TT><B>$</B></TT>mon has the range 0..11 and
|
|
<TT><B>$</B></TT>wday has the range 0..6.
|
|
|
|
<DT><B>hex</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Returns the decimal value of <FONT SIZE="-1">EXPR</FONT> interpreted as a hex string.
|
|
|
|
<DT><B>localtime</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Converts a time as returned by the <B>time</B> function to
|
|
<I>ctime</I>(3) string.
|
|
In array context, returns a 9-element array with the time analyzed for the local time zone.
|
|
|
|
<DT><B>oct</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Returns the decimal value of <FONT SIZE="-1">EXPR</FONT> interpreted as an octal string.
|
|
If <FONT SIZE="-1">EXPR</FONT> starts off with <TT><B>0x</B></TT>, interprets it as a hex string
|
|
instead.
|
|
|
|
<DT><B>ord</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Returns the ASCII value of the first character of <FONT SIZE="-1">EXPR</FONT>.
|
|
|
|
<DT><B>vec</B> <FONT SIZE="-1">EXPR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">OFFSET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">BITS</FONT>
|
|
<DD>Treats string <FONT SIZE="-1">EXPR</FONT> as a vector of unsigned integers,
|
|
and yields the bit at <FONT SIZE="-1">OFFSET</FONT>.
|
|
<FONT SIZE="-1">BITS</FONT> must be between 1 and 32.
|
|
May be assigned to.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="structure"></A>
|
|
<H2>Structure Conversion</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>pack</B> <FONT SIZE="-1">TEMPLATE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Packs the values into a binary structure using <FONT SIZE="-1">TEMPLATE</FONT>.
|
|
|
|
<DT><B>unpack</B> <FONT SIZE="-1">TEMPLATE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Unpacks the structure <FONT SIZE="-1">EXPR</FONT> into an array,
|
|
using <FONT SIZE="-1">TEMPLATE</FONT>.
|
|
|
|
</DL>
|
|
|
|
<P><FONT SIZE="-1">TEMPLATE</FONT> is a sequence of characters as follows:</P>
|
|
|
|
<UL>
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR><TD><TT><B>a</B></TT> / <TT><B>A </B></TT></TD>
|
|
<TD>ASCII string, null- / space-padded</TD></TR>
|
|
|
|
<TR><TD><TT><B>b</B></TT> / <TT><B>B</B></TT></TD>
|
|
<TD>Bit string in ascending / descending order</TD></TR>
|
|
|
|
<TR><TD><TT><B>c</B></TT> / <TT><B>C</B></TT></TD>
|
|
<TD>Native / unsigned char value</TD></TR>
|
|
|
|
<TR><TD><TT><B>f</B></TT> / <TT><B>d</B></TT></TD>
|
|
<TD>Single / double float in native format</TD></TR>
|
|
|
|
<TR><TD><TT><B>h</B></TT> / <TT><B>H</B></TT></TD>
|
|
<TD>Hex string, low / high nybble first</TD></TR>
|
|
|
|
<TR><TD><TT><B>i</B></TT> / <TT><B>I</B></TT></TD>
|
|
<TD>Signed / unsigned integer value</TD></TR>
|
|
|
|
<TR><TD><TT><B>l</B></TT> / <TT><B>L</B></TT></TD>
|
|
<TD>Signed / unsigned long value</TD></TR>
|
|
|
|
<TR><TD><TT><B>n</B></TT> / <TT><B>N</B></TT></TD>
|
|
<TD>Short / long in network (big endian) byte order</TD></TR>
|
|
|
|
<TR><TD><TT><B>s</B></TT> / <TT><B>S</B></TT></TD>
|
|
<TD>Signed / unsigned short value</TD></TR>
|
|
|
|
<TR><TD><TT><B>u</B></TT> / <TT><B>P</B></TT></TD>
|
|
<TD>Uuencoded string / pointer to a string</TD></TR>
|
|
|
|
<TR><TD><TT><B>v</B></TT> / <TT><B>V</B></TT></TD>
|
|
<TD>Short / long in VAX (little endian) byte order</TD></TR>
|
|
|
|
<TR><TD><TT><B>x</B></TT> / <TT><B>@</B></TT></TD>
|
|
<TD>Null byte / null fill until position</TD></TR>
|
|
|
|
<TR><TD><TT><B>X</B></TT></TD>
|
|
<TD>Backup a byte</TD></TR>
|
|
|
|
</TABLE>
|
|
</UL>
|
|
|
|
<P>Each character may be followed by a decimal number that
|
|
will be used as a repeat count; an asterisk (<TT><B>*</B></TT>) specifies all
|
|
remaining arguments. If the format is preceded with <TT><B>%</B></TT><FONT SIZE="-1">N</FONT>,
|
|
<B>unpack</B> returns an <FONT SIZE="-1">N</FONT>-bit checksum instead. Spaces may be
|
|
included in the template for readability purposes.</P>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="string"></A>
|
|
<H2>String Functions</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>chomp</B> <FONT SIZE="-1">LIST†</FONT>
|
|
<DD>Removes line endings from all elements of the list;
|
|
returns the (total) number of characters removed.
|
|
|
|
<DT><B>chop</B> <FONT SIZE="-1">LIST†</FONT>
|
|
<DD>Chops off the last character on all elements of the
|
|
list; returns the last chopped character.
|
|
|
|
<DT><B>crypt</B> <FONT SIZE="-1">PLAINTEXT</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SALT</FONT>
|
|
<DD>Encrypts a string.
|
|
|
|
<DT><B>eval</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD><FONT SIZE="-1">EXPR</FONT> is parsed and executed as if it were a Perl program.
|
|
The value returned is the value of the last expression evaluated.
|
|
If there is a syntax error or runtime error,
|
|
an undefined string is returned by <B>eval</B>, and
|
|
<TT><B>$@</B></TT> is set to the error message.
|
|
See also <B>eval</B> in section <A HREF="#miscellaneous">Miscellaneous</A>.
|
|
|
|
<DT><B>index</B> <FONT SIZE="-1">STR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SUBSTR</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">OFFSET</FONT> ]
|
|
<DD>Returns the position of <FONT SIZE="-1">SUBSTR</FONT>
|
|
in <FONT SIZE="-1">STR</FONT> at or after <FONT SIZE="-1">OFFSET</FONT>.
|
|
If the substring is not found, returns <TT><B>-1</B></TT>
|
|
(but see <TT><B>$[</B></TT> in section <A HREF="#specialvariables">Special Variables</A>).
|
|
|
|
<DT><B>length</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Returns the length in characters of the value of <FONT SIZE="-1">EXPR</FONT>.
|
|
|
|
<DT><B>lc</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Returns a lowercase version of <FONT SIZE="-1">EXPR</FONT>.
|
|
|
|
<DT><B>lcfirst</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Returns <FONT SIZE="-1">EXPR</FONT> with the first character lowercase.
|
|
|
|
<DT><B>quotemeta</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Returns <FONT SIZE="-1">EXPR</FONT> with all regular expression metacharacters quoted.
|
|
|
|
<DT><B>rindex</B> <FONT SIZE="-1">STR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SUBSTR</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">OFFSET</FONT> ]
|
|
<DD>Returns the position of the last <FONT SIZE="-1">SUBSTR</FONT>
|
|
in <FONT SIZE="-1">STR</FONT> at or before <FONT SIZE="-1">OFFSET</FONT>.
|
|
|
|
<DT><B>substr</B> <FONT SIZE="-1">EXPR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">OFFSET</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">LEN</FONT> ]
|
|
<DD>Extracts a substring of length <FONT SIZE="-1">LEN</FONT> out of <FONT SIZE="-1">EXPR</FONT>
|
|
and returns it. If <FONT SIZE="-1">OFFSET</FONT> is negative, counts from the end of
|
|
the string. May be assigned to.
|
|
|
|
<DT><B>uc</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Returns an uppercased version of <FONT SIZE="-1">EXPR</FONT>.
|
|
|
|
<DT><B>ucfirst</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Returns <FONT SIZE="-1">EXPR</FONT> with the first character uppercased.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="array"></A>
|
|
<H2>Array and List Functions</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>delete</B> <TT><B>$</B></TT><FONT SIZE="-1">HASH</FONT><TT><B>{</B></TT><FONT SIZE="-1">KEY</FONT><TT><B>}</B></TT>
|
|
<DD>Deletes the specified value from the specified hash.
|
|
Returns the deleted value unless <FONT SIZE="-1">HASH</FONT> is <B>tie</B>d
|
|
to a package that does not support this.
|
|
|
|
<DT><B>each</B> <TT><B>%</B></TT><FONT SIZE="-1">HASH</FONT>
|
|
<DD>Returns a 2-element array consisting of the key and value for the next value
|
|
of the hash. Entries are returned in an apparently random order.
|
|
After all values of the hash have been returned, a null array is
|
|
returned. The next call to <B>each</B> after that will start iterating again.
|
|
|
|
<DT><B>exists</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Checks if the specified hash key exists in its hash array.
|
|
|
|
<DT><B>grep</B> <FONT SIZE="-1">EXPR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT>
|
|
<BR><B>grep</B> <FONT SIZE="-1">BLOCK</FONT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Evaluates <FONT SIZE="-1">EXPR</FONT> or <FONT SIZE="-1">BLOCK</FONT> for each element of the <FONT SIZE="-1">LIST</FONT>,
|
|
locally setting <TT><B>$_</B></TT> to refer to the element.
|
|
Modifying <TT><B>$_</B></TT> will modify the
|
|
corresponding element from <FONT SIZE="-1">LIST</FONT>.
|
|
Returns the array of elements from
|
|
<FONT SIZE="-1">LIST</FONT> for which <FONT SIZE="-1">EXPR</FONT> returned <B>true</B>.
|
|
|
|
<DT><B>join</B> <FONT SIZE="-1">EXPR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Joins the separate strings of <FONT SIZE="-1">LIST</FONT> into a single string with fields
|
|
separated by the value of <FONT SIZE="-1">EXPR</FONT>, and returns the string.
|
|
|
|
<DT><B>keys</B> <TT><B>%</B></TT><FONT SIZE="-1">HASH</FONT>
|
|
<DD>Returns an array with of all the keys of the named hash.
|
|
|
|
<DT><B>map</B> <FONT SIZE="-1">EXPR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT>
|
|
<BR><B>map</B> <FONT SIZE="-1">BLOCK</FONT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Evaluates <FONT SIZE="-1">EXPR</FONT> or <FONT SIZE="-1">BLOCK</FONT> for each element of the <FONT SIZE="-1">LIST</FONT>,
|
|
locally setting <TT><B>$_</B></TT> to refer to the element.
|
|
Modifying <TT><B>$_</B></TT> will modify the
|
|
corresponding element from <FONT SIZE="-1">LIST</FONT>.
|
|
Returns the list of results.
|
|
|
|
<DT><B>pop</B> <TT><B>@</B></TT><FONT SIZE="-1">ARRAY</FONT>
|
|
<DD>Pops off and returns the last value of the array.
|
|
|
|
<DT><B>push</B> <TT><B>@</B></TT><FONT SIZE="-1">ARRAY</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Pushes the values of <FONT SIZE="-1">LIST</FONT> onto the end of the array.
|
|
|
|
<DT><B>reverse</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>In array context, returns the <FONT SIZE="-1">LIST</FONT> in reverse order.
|
|
In scalar context: returns the first element of <FONT SIZE="-1">LIST</FONT>
|
|
with bytes reversed.
|
|
|
|
<DT><B>scalar</B> <TT><B>@</B></TT><FONT SIZE="-1">ARRAY</FONT>
|
|
<DD>Returns the number of elements in the array.
|
|
|
|
<DT><B>scalar</B> <TT><B>%</B></TT><FONT SIZE="-1">HASH</FONT>
|
|
<DD>Returns a <B>true</B> value if the hash has elements defined.
|
|
|
|
<DT><B>shift</B> [ <TT><B>@</B></TT><FONT SIZE="-1">ARRAY</FONT> ]
|
|
<DD>Shifts the first value of the array off and returns it, shortening the array
|
|
by 1 and moving everything down. If <TT><B>@</B></TT><FONT SIZE="-1">ARRAY</FONT> is omitted,
|
|
shifts <TT><B>@ARGV</B></TT> in main and <TT><B>@_</B></TT> in subroutines.
|
|
|
|
<DT><B>sort</B> [ <FONT SIZE="-1">SUBROUTINE</FONT> ] <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Sorts the <FONT SIZE="-1">LIST</FONT> and returns the sorted array value.
|
|
<FONT SIZE="-1">SUBROUTINE</FONT>, if specified, must return less than zero,
|
|
zero, or greater than zero, depending on how the
|
|
elements of the array (available to the routine as <TT><B>$a</B></TT> and <TT><B>$b</B></TT>)
|
|
are to be ordered. <FONT SIZE="-1">SUBROUTINE</FONT> may be the name of a user-defined
|
|
routine, or a <FONT SIZE="-1">BLOCK</FONT>.
|
|
|
|
<DT><B>splice</B> <TT><B>@</B></TT><FONT SIZE="-1">ARRAY</FONT><TT><B>,</B></TT> <FONT SIZE="-1">OFFSET</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">LENGTH</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT> ] ]
|
|
<DD>Removes the elements of <TT><B>@</B></TT><FONT SIZE="-1">ARRAY</FONT> designated by
|
|
<FONT SIZE="-1">OFFSET</FONT> and <FONT SIZE="-1">LENGTH</FONT>,
|
|
and replaces them with <FONT SIZE="-1">LIST</FONT> (if specified).
|
|
Returns the elements removed.
|
|
|
|
<DT><B>split</B> [ <FONT SIZE="-1">PATTERN</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">EXPR†</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">LIMIT</FONT> ] ] ]
|
|
<DD>Splits a string into an array of strings, and returns it.
|
|
If <FONT SIZE="-1">LIMIT</FONT> is specified, splits into at most that number
|
|
of fields. If <FONT SIZE="-1">PATTERN</FONT> is also omitted, splits at the whitespace.
|
|
If not in array context, returns number of fields and splits to <TT><B>@_</B></TT>.
|
|
See also <A HREF="#search">Search and Replace Functions</A>.
|
|
|
|
<DT><B>unshift</B> <TT><B>@</B></TT><FONT SIZE="-1">ARRAY</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Prepends list to the front of the array, and returns the number of elements in
|
|
the new array.
|
|
|
|
<DT><B>values</B> <TT><B>%</B></TT><FONT SIZE="-1">HASH</FONT>
|
|
<DD>Returns a normal array consisting of all the values of the named hash.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="regular"></A>
|
|
<H2>Regular Expressions</H2>
|
|
|
|
<P>Each character matches itself, unless it is one of the special characters
|
|
<TT><B>+ ? . * ^ $ ( ) [ ] { } | \</B></TT>.
|
|
The special meaning of these characters can be escaped using a <TT><B>\</B></TT>.</P>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR><TD VALIGN=top><TT><B>.</B></TT></TD>
|
|
<TD VALIGN=top>matches an arbitrary character, but not a newline
|
|
unless it is a single-line match (see <B>m//s</B>).</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>(</B></TT>...<TT><B>)</B></TT></TD>
|
|
<TD>groups a series of pattern elements to a single element.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>^</B></TT></TD>
|
|
<TD VALIGN=top>matches the beginning of the target. In multiline mode
|
|
(see <B>m//m</B>) also matches after every newline character.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$</B></TT></TD>
|
|
<TD>matches the end of the line.
|
|
In multiline mode also matches before every newline character.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>[</B></TT> ... <TT><B>]</B></TT></TD>
|
|
<TD>denotes a class of characters to match.
|
|
<TT><B>[^</B></TT> ... <TT><B>]</B></TT> negates the class.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>(</B></TT> ... <TT><B>|</B></TT> ... <TT><B>|</B></TT> ... <TT><B>)</B></TT></TD>
|
|
<TD>matches one of the alternatives.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>(?#</B></TT> <FONT SIZE="-1">TEXT</FONT> <TT><B>)</B></TT></TD>
|
|
<TD>Comment.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>(?:</B></TT> <FONT SIZE="-1">REGEXP</FONT> <TT><B>)</B></TT></TD>
|
|
<TD>Like <TT><B>(</B></TT><FONT SIZE="-1">REGEXP</FONT><TT><B>)</B></TT> but does not make back-references.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>(?=</B></TT> <FONT SIZE="-1">REGEXP</FONT> <TT><B>)</B></TT></TD>
|
|
<TD>Zero width positive look-ahead assertion.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>(?!</B></TT> <FONT SIZE="-1">REGEXP</FONT> <TT><B>)</B></TT></TD>
|
|
<TD>Zero width negative look-ahead assertion.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>(?</B></TT> <FONT SIZE="-1">MODIFIER</FONT> <TT><B>)</B></TT></TD>
|
|
<TD>Embedded pattern-match modifier. <FONT SIZE="-1">MODIFIER</FONT> can be one or more of
|
|
<B>i</B>, <B>m</B>, <B>s</B>, or <B>x</B>.</TD></TR>
|
|
|
|
<TR><TD COLSPAN=2><BR>Quantified subpatterns match as many times as possible.
|
|
When followed with a <TT><B>?</B></TT> they match the minimum number of times.
|
|
These are the quantifiers:<BR><BR></TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>+</B></TT></TD>
|
|
<TD>matches the preceding pattern element one or more times.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>?</B></TT></TD>
|
|
<TD>matches zero or one times.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>*</B></TT></TD>
|
|
<TD>matches zero or more times.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>{</B></TT><FONT SIZE="-1">N</FONT><TT><B>,</B></TT><FONT SIZE="-1">M</FONT><TT><B>}</B></TT></TD>
|
|
<TD>denotes the minimum <FONT SIZE="-1">N</FONT> and maximum <FONT SIZE="-1">M</FONT> match count.
|
|
<TT><B>{</B></TT><FONT SIZE="-1">N</FONT><TT><B>}</B></TT> means exactly <FONT SIZE="-1">N</FONT> times;
|
|
<TT><B>{</B></TT><FONT SIZE="-1">N</FONT><TT><B>,</B></TT><TT><B>}</B></TT> means at least <FONT SIZE="-1">N</FONT> times.</TD></TR>
|
|
|
|
<TR><TD COLSPAN=2><BR>A <TT><B>\</B></TT> escapes any special meaning
|
|
of the following character if non-alphanumeric, but it turns most alphanumeric characters
|
|
into something special:<BR><BR></TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>\w</B></TT></TD>
|
|
<TD>matches alphanumeric, including <TT><B>_</B></TT>,
|
|
<TT><B>\W</B></TT> matches non-alphanumeric.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>\s</B></TT></TD>
|
|
<TD>matches whitespace, <TT><B>\S</B></TT> matches non-whitespace.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>\d</B></TT></TD>
|
|
<TD>matches numeric, <TT><B>\D</B></TT> matches non-numeric.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>\A</B></TT></TD>
|
|
<TD>matches the beginning of the string, <TT><B>\Z</B></TT> matches the end.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>\b</B></TT></TD>
|
|
<TD>matches word boundaries, <TT><B>\B</B></TT> matches non-boundaries.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>\G</B></TT></TD>
|
|
<TD>matches where the previous <B>m//g</B> search left off.</TD></TR>
|
|
|
|
<TR><TD><TT><B>\n</B></TT>, <TT><B>\r</B></TT>, <TT><B>\f</B></TT>, <TT><B>\t</B></TT></TD>
|
|
<TD>etc. have their usual meaning.</TD></TR>
|
|
|
|
<TR><TD><TT><B>\w</B></TT>, <TT><B>\s</B></TT> and <TT><B>\d</B></TT></TD>
|
|
<TD>may be used within character classes,
|
|
<TT><B>\b</B></TT> denotes backspace in this context.</TD></TR>
|
|
|
|
<TR><TD COLSPAN=2><BR>Back-references:<BR><BR></TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>\1</B></TT> ... <TT><B>\9</B></TT></TD>
|
|
<TD>refer to matched subexpressions, grouped with <TT><B>()</B></TT>,
|
|
inside the match.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>\10</B></TT></TD>
|
|
<TD>and up can also be used if the pattern matches that many subexpressions.</TD></TR>
|
|
|
|
</TABLE>
|
|
|
|
<P>See also <TT><B>$1</B></TT> ... <TT><B>$9</B></TT>,<TT><B> $+</B></TT>,<TT><B> $&</B></TT>,<TT><B> $`</B></TT>, and<TT><B> $' </B></TT>
|
|
in section <A HREF="#specialvariables">Special Variables</A>.</P>
|
|
|
|
<P>With modifier <B>x</B>, whitespace can be used in the patterns for
|
|
readability purposes.</P>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="search"></A>
|
|
<H2>Search and Replace Functions</H2>
|
|
|
|
<DL>
|
|
|
|
<DT>[ <FONT SIZE="-1">EXPR</FONT> <TT><B>=~</B></TT> ] [ <B>m</B> ] <TT><B>/</B></TT><FONT SIZE="-1">PATTERN</FONT><TT><B>/</B></TT>
|
|
[ <B>g</B> ] [ <B>i</B> ] [ <B>m</B> ] [ <B>o</B> ] [ <B>v</B> ] [ <B>x</B> ]
|
|
<DD>Searches <FONT SIZE="-1">EXPR</FONT> (default: <TT><B>$_</B></TT>) for a pattern. If you
|
|
prepend an <B>m</B> you can use almost any pair of delimiters
|
|
instead of the slashes. If used in array context,
|
|
an array is returned consisting of the subexpressions
|
|
matched by the parentheses in the pattern, i.e., <TT><B>($1,$2,$3,</B></TT>...<TT><B>)</B></TT>.
|
|
<BR>
|
|
Optional modifiers: <B>g</B> matches as many times as
|
|
possible; <B>i</B> searches in a case-insensitive manner; <B>o</B>
|
|
interpolates variables only once. <B>m</B> treats the string
|
|
as multiple lines; <B>s</B> treats the string as a single line; <B>x</B>
|
|
allows for regular expression extensions.
|
|
<BR>
|
|
If <FONT SIZE="-1">PATTERN</FONT> is empty, the most recent pattern from a
|
|
previous match or replacement is used.
|
|
<BR>
|
|
With <B>g</B> the match can be used as an iterator in scalar
|
|
context.
|
|
|
|
<DT><TT><B>?</B></TT><FONT SIZE="-1">PATTERN</FONT><TT><B>?</B></TT>
|
|
<DD>This is just like the <TT><B>/</B></TT><FONT SIZE="-1">PATTERN</FONT><TT><B>/</B></TT> search, except that it
|
|
matches only once between calls to the <B>reset</B> operator.
|
|
|
|
<DT>[ <TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT> <TT><B>=~</B></TT> ] <B>s</B><TT><B>/</B></TT><FONT SIZE="-1">PATTERN</FONT><TT><B>/</B></TT><FONT SIZE="-1">REPLACEMENT</FONT><TT><B>/</B></TT>
|
|
[ <B>e</B> ] [ <B>g</B> ] [ <B>i</B> ] [ <B>m</B> ] [ <B>o</B> ] [ <B>s</B> ] [ <B>x</B> ]
|
|
<DD>Searches a string for a pattern, and if found, replaces
|
|
that pattern with the replacement text. It returns the
|
|
number of substitutions made, if any; if no substitutions are made, it
|
|
returns <STRONG>false</STRONG>.
|
|
<BR>
|
|
Optional modifiers: <B>g</B> replaces all occurrences of the
|
|
pattern; <B>e</B> evaluates the replacement string as a Perl
|
|
expression; for any other modifiers, see <TT><B>/</B></TT><FONT SIZE="-1">PATTERN</FONT><TT><B>/</B></TT>
|
|
matching. Almost any delimiter may replace the
|
|
slashes; if single quotes are used, no interpretation is
|
|
done on the strings between the delimiters, otherwise
|
|
the strings are interpolated as if inside double quotes.
|
|
<BR>
|
|
If bracketing delimiters are used, <FONT SIZE="-1">PATTERN</FONT> and
|
|
<FONT SIZE="-1">REPLACEMENT</FONT> may have their own delimiters, e.g.,
|
|
<TT><B>s(foo)[bar]</B></TT>. If <FONT SIZE="-1">PATTERN</FONT> is empty, the most recent pattern
|
|
from a previous match or replacement is used.
|
|
|
|
<DT>[ <TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT> <TT><B>=~</B></TT> ] <B>tr</B><TT><B>/</B></TT><FONT SIZE="-1">SEARCHLIST</FONT><TT><B>/</B></TT><FONT SIZE="-1">REPLACEMENTLIST</FONT><TT><B>/</B></TT>
|
|
[ <B>c</B> ] [ <B>d</B> ] [ <B>s</B> ]
|
|
<DD>Translates all occurrences of the characters found in
|
|
the search list with the corresponding character in
|
|
the replacement list. It returns the number of characters
|
|
replaced. <B>y</B> may be used instead of <B>tr</B>.
|
|
<BR>
|
|
Optional modifiers: <B>c</B> complements the <FONT SIZE="-1">SEARCHLIST</FONT>;
|
|
<B>d</B> deletes all characters found in <FONT SIZE="-1">SEARCHLIST</FONT> that do
|
|
not have a corresponding character in
|
|
<FONT SIZE="-1">REPLACEMENTLIST</FONT>; <B>s</B> squeezes all
|
|
sequences of characters that are translated into the same target character
|
|
into one occurrence of this character.
|
|
|
|
<DT><B>pos</B> <FONT SIZE="-1">SCALAR</FONT>
|
|
<DD>Returns the position where the last <B>m//g</B> search left off
|
|
for <FONT SIZE="-1">SCALAR</FONT>. May be assigned to.
|
|
|
|
<DT><B>study</B> [ <TT><B>$</B></TT><FONT SIZE="-1">VAR†</FONT> ]
|
|
<DD>Study the scalar variable <TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT> in anticipation of
|
|
performing many pattern matches on its contents
|
|
before the variable is next modified.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="filetest"></A>
|
|
<H2>File Test Operators</H2>
|
|
|
|
These unary operators takes one argument, either a filename
|
|
or a filehandle, and test the associated file to see if something
|
|
is true about it. If the argument is omitted, they test <TT><B>$_</B></TT>
|
|
(except for <TT><B>-t</B></TT>, which tests <TT><B>STDIN</B></TT>). If the special argument <TT><B>_</B></TT>
|
|
(underscore) is passed, they use the information from the preceding test or <B>stat</B> call.
|
|
<P>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR><TD VALIGN=top NOWRAP><TT><B>-r -w -x </B></TT></TD>
|
|
<TD VALIGN=top>File is readable/writable/executable by effective uid/gid.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top NOWRAP><TT><B>-R -W -X</B></TT></TD>
|
|
<TD VALIGN=top>File is readable/writable/executable by real uid/gid.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top NOWRAP><TT><B>-o -O</B></TT></TD>
|
|
<TD VALIGN=top>File is owned by effective/real uid.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-e -z</B></TT></TD>
|
|
<TD VALIGN=top>File exists/has zero size.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-s</B></TT></TD>
|
|
<TD VALIGN=top>File exists and has non-zero size. Returns the size.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-f -d</B></TT></TD>
|
|
<TD VALIGN=top>File is a plain file/a directory.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-l -S -p</B></TT></TD>
|
|
<TD VALIGN=top>File is a symbolic link/a socket/a named pipe (FIFO).</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-b -c</B></TT></TD>
|
|
<TD VALIGN=top>File is a block/character special file.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-u -g -k</B></TT></TD>
|
|
<TD VALIGN=top>File has setuid/setgid/sticky bit set.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-t</B></TT></TD>
|
|
<TD VALIGN=top>Tests if filehandle (<TT><B>STDIN</B></TT> by default) is opened to a tty.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-T -B</B></TT></TD>
|
|
<TD VALIGN=top>File is a text/non-text (binary) file.
|
|
<TT><B>-T</B></TT> and <TT><B>-B</B></TT> return <B>true</B> on a null file,
|
|
or a file at EOF when testing a filehandle.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-M -A -C</B></TT></TD>
|
|
<TD VALIGN=top>File modification / access / inode-change time.
|
|
Measured in days. Value returned reflects the file age at
|
|
the time the script started. See also <TT><B>$^T</B></TT> in the section
|
|
<A HREF="#specialvariables">Special Variables</A>.</TD></TR>
|
|
|
|
</TABLE>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="fileoperations"></A>
|
|
<H2>File Operations</H2>
|
|
|
|
Functions operating on a list of files return the number of files successfully
|
|
operated upon.
|
|
|
|
<DL>
|
|
|
|
<DT><B>chmod</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Changes the permissions of a list of files.
|
|
The first element of the list must be the numerical mode.
|
|
|
|
<DT><B>chown</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Changes the owner and group of a list of files.
|
|
The first two elements of the list must be the numerical uid and gid.
|
|
|
|
<DT><B>truncate</B> <FONT SIZE="-1">FILE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SIZE</FONT>
|
|
<DD>Truncates <FONT SIZE="-1">FILE</FONT> to <FONT SIZE="-1">SIZE</FONT>.
|
|
<FONT SIZE="-1">FILE</FONT> may be a filename or a filehandle.
|
|
|
|
<DT><B>link</B> <FONT SIZE="-1">OLDFILE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">NEWFILE</FONT>
|
|
<DD>Creates a new filename linked to the old filename.
|
|
|
|
<DT><B>lstat</B> <FONT SIZE="-1">FILE</FONT>
|
|
<DD>Like <B>stat</B>, but does not traverse a final symbolic link.
|
|
|
|
<DT><B>mkdir</B> <FONT SIZE="-1">DIR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">MODE</FONT>
|
|
<DD>Creates a directory with given permissions.
|
|
Sets <TT><B>$!</B></TT> on failure.
|
|
|
|
<DT><B>readlink</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Returns the value of a symbolic link.
|
|
|
|
<DT><B>rename</B> <FONT SIZE="-1">OLDNAME</FONT><TT><B>,</B></TT> <FONT SIZE="-1">NEWNAME</FONT>
|
|
<DD>Changes the name of a file.
|
|
|
|
<DT><B>rmdir</B> <FONT SIZE="-1">FILENAME†</FONT>
|
|
<DD>Deletes the directory if it is empty.
|
|
Sets <TT><B>$!</B></TT> on failure.
|
|
|
|
<DT><B>stat</B> <FONT SIZE="-1">FILE</FONT>
|
|
<DD>Returns a 13-element array
|
|
(0: <TT><B>$</B></TT>dev,
|
|
1: <TT><B>$</B></TT>ino,
|
|
2: <TT><B>$</B></TT>mode,
|
|
3: <TT><B>$</B></TT>nlink,
|
|
4: <TT><B>$</B></TT>uid,
|
|
5: <TT><B>$</B></TT>gid,
|
|
6: <TT><B>$</B></TT>rdev,
|
|
7: <TT><B>$</B></TT>size,
|
|
8: <TT><B>$</B></TT>atime,
|
|
9: <TT><B>$</B></TT>mtime,
|
|
10: <TT><B>$</B></TT>ctime,
|
|
11: <TT><B>$</B></TT>blksize,
|
|
12: <TT><B>$</B></TT>blocks).
|
|
<FONT SIZE="-1">FILE</FONT> can be a filehandle, an expression evaluating to a filename,
|
|
or <TT><B>_</B></TT> to refer to the last file test operation or <B>stat</B> call.
|
|
Returns a null list if the <B>stat</B> fails.
|
|
|
|
<DT><B>symlink</B> <FONT SIZE="-1">OLDFILE</FONT>, <FONT SIZE="-1">NEWFILE</FONT>
|
|
<DD>Creates a new filename symbolically linked to the old filename.
|
|
|
|
<DT><B>unlink</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Deletes a list of files.
|
|
|
|
<DT><B>utime</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Changes the access and modification times.
|
|
The first two elements of the list must be the numerical access and modification times.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="input"></A>
|
|
<H2>Input / Output</H2>
|
|
|
|
In input/output operations, <FONT SIZE="-1">FILEHANDLE</FONT> may be a
|
|
filehandle as opened by the <B>open</B> operator, a predefined filehandle
|
|
(e.g., <TT><B>STDOUT</B></TT>) or a scalar variable that evaluates to the name of a
|
|
filehandle to be used.
|
|
|
|
<DL>
|
|
|
|
<DT><TT><B><</B></TT><FONT SIZE="-1">FILEHANDLE</FONT><TT><B>></B></TT>
|
|
<DD>In scalar context, reads a single line from the file opened on <FONT SIZE="-1">FILEHANDLE</FONT>.
|
|
In array context, reads the whole file.
|
|
|
|
<DT><TT><B><</B></TT> <TT><B>></B></TT>
|
|
<DD>Reads from the input stream formed by the files specified in
|
|
<TT><B>@ARGV</B></TT>, or standard input if no arguments were supplied.
|
|
|
|
<DT><B>binmode</B> <FONT SIZE="-1">FILEHANDLE</FONT>
|
|
<DD>Arranges for the file opened on <FONT SIZE="-1">FILEHANDLE</FONT> to be read
|
|
or written in <I>binary</I> mode as opposed to <I>text</I> mode (null operation on UNIX).
|
|
|
|
<DT><B>close</B> <FONT SIZE="-1">FILEHANDLE</FONT>
|
|
<DD>Closes the file or pipe associated with the filehandle.
|
|
|
|
<DT><B>dbmclose</B> <TT><B>%</B></TT><FONT SIZE="-1">HASH</FONT>
|
|
<DD>Depreciated, use <B>untie</B> instead.
|
|
|
|
<DT><B>dbmopen</B> <TT><B>%</B></TT><FONT SIZE="-1">HASH</FONT><TT><B>,</B></TT> <FONT SIZE="-1">DBMNAME</FONT><TT><B>,</B></TT> <FONT SIZE="-1">MODE</FONT>
|
|
<DD>Depreciated, use <B>tie</B> instead.
|
|
|
|
<DT><B>eof</B> <FONT SIZE="-1">FILEHANDLE</FONT>
|
|
<DD>Returns <B>true</B> if the next read will return end of file, or
|
|
if the file is not open.
|
|
|
|
<DT><B>eof</B>
|
|
<DD>Returns the EOF status for the last file read.
|
|
|
|
<DT><B>eof</B><TT><B>()</B></TT>
|
|
<DD>Indicates EOF on the pseudo file formed of the files
|
|
listed on the command line.
|
|
|
|
<DT><B>fcntl</B> <FONT SIZE="-1">FILEHANDLE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FUNCTION</FONT><TT><B>,</B></TT> <TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT>
|
|
<DD>Implements the <I>fcntl</I>(2) function. This function has
|
|
non-standard return values.
|
|
|
|
<DT><B>fileno</B> <FONT SIZE="-1">FILEHANDLE</FONT>
|
|
<DD>Returns the file descriptor for a given (open) file.
|
|
|
|
<DT><B>flock</B> <FONT SIZE="-1">FILEHANDLE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">OPERATION</FONT>
|
|
<DD>Calls <I>flock</I>(2) on the file.
|
|
<FONT SIZE="-1">OPERATION</FONT> formed by
|
|
adding 1 (shared),
|
|
2 (exclusive), 4 (non-blocking), or 8 (unlock).
|
|
|
|
<DT><B>getc</B> [ <FONT SIZE="-1">FILEHANDLE</FONT> ]
|
|
<DD>Yields the next character from the file, or an empty
|
|
string on end of file. If <FONT SIZE="-1">FILEHANDLE</FONT> is omitted, reads
|
|
from <TT><B>STDIN</B></TT>.
|
|
|
|
<DT><B>ioctl</B> <FONT SIZE="-1">FILEHANDLE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FUNCTION</FONT><TT><B>,</B></TT> <TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT>
|
|
<DD>Performs <I>ioctl</I>(2) on the file. This function has non-standard
|
|
return values.
|
|
|
|
<DT><B>open</B> <FONT SIZE="-1">FILEHANDLE</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">FILENAME</FONT> ]
|
|
<DD>Opens a file and associates it with <FONT SIZE="-1">FILEHANDLE</FONT>. If
|
|
<FONT SIZE="-1">FILENAME</FONT> is omitted, the scalar variable of the same
|
|
name as the <FONT SIZE="-1">FILEHANDLE</FONT> must contain the filename.
|
|
<BR>
|
|
The following filename conventions apply when
|
|
opening a file.
|
|
<BR>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR><TD><TT><B>"</B></TT><FONT SIZE="-1">FILE</FONT><TT><B>"</B></TT></TD>
|
|
<TD>open <FONT SIZE="-1">FILE</FONT> for input.
|
|
Also <TT><B>"<</B></TT><FONT SIZE="-1">FILE</FONT><TT><B>"</B></TT>.</TD></TR>
|
|
|
|
<TR><TD><TT><B>"></B></TT><FONT SIZE="-1">FILE</FONT><TT><B>"</B></TT></TD>
|
|
<TD>open <FONT SIZE="-1">FILE</FONT> for output, creating it if necessary.</TD></TR>
|
|
|
|
<TR><TD><TT><B>">></B></TT><FONT SIZE="-1">FILE</FONT><TT><B>"</B></TT></TD>
|
|
<TD>open <FONT SIZE="-1">FILE</FONT> in append mode.</TD></TR>
|
|
|
|
<TR><TD><TT><B>"+></B></TT><FONT SIZE="-1">FILE</FONT><TT><B>"</B></TT></TD>
|
|
<TD>open <FONT SIZE="-1">FILE</FONT> with read/write access.</TD></TR>
|
|
|
|
<TR><TD><TT><B>"|</B></TT><FONT SIZE="-1">CMD</FONT><TT><B>"</B></TT></TD>
|
|
<TD>opens a pipe to command <FONT SIZE="-1">CMD</FONT>;
|
|
forks if <FONT SIZE="-1">CMD</FONT> is <TT><B>-</B></TT>.</TD></TR>
|
|
|
|
<TR><TD><TT><B>"</B></TT><FONT SIZE="-1">CMD</FONT><TT><B>|"</B></TT></TD>
|
|
<TD>opens a pipe from command <FONT SIZE="-1">CMD</FONT>;
|
|
forks if <FONT SIZE="-1">CMD</FONT> is <TT><B>-</B></TT>.</TD></TR>
|
|
|
|
</TABLE>
|
|
|
|
<FONT SIZE="-1">FILE</FONT> may be <TT><B>&</B></TT><FONT SIZE="-1">FILEHND</FONT>
|
|
in which case the new filehandle is connected to the (previously opened)
|
|
filehandle <FONT SIZE="-1">FILEHND</FONT>.
|
|
If it is <TT><B>&=</B></TT><FONT SIZE="-1">N</FONT>, <FONT SIZE="-1">FILE</FONT> will be connected to the given file descriptor.
|
|
<B>open</B> returns <B>undef</B> upon failure, <B>true</B> otherwise.
|
|
|
|
<DT><B>pipe</B> <FONT SIZE="-1">READHANDLE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">WRITEHANDLE</FONT><TT><B>)</B></TT>
|
|
<DD>Returns a pair of connected pipes.
|
|
|
|
<DT><B>print</B> [ <FONT SIZE="-1">FILEHANDLE</FONT> ] [ <FONT SIZE="-1">LIST†</FONT> ]
|
|
<DD>Equivalent to <B>print</B> <FONT SIZE="-1">FILEHANDLE</FONT> <B>sprintf</B> <FONT SIZE="-1">LIST</FONT>.
|
|
|
|
<DT><B>printf</B>[<TT><B>(</B></TT>[<FONT SIZE="-1">FILEHANDLE</FONT>] <FONT SIZE="-1">LIST†</FONT><TT><B>)</B></TT>*]
|
|
<DD>Equivalent to <B>print</B> <FONT SIZE="-1">FILEHANDLE</FONT>
|
|
<B>sprintf</B><TT><B>(</B></TT><FONT SIZE="-1">LIST</FONT><TT><B>)</B></TT>.
|
|
|
|
<DT><B>read</B> <FONT SIZE="-1">FILEHANDLE</FONT><TT><B>,</B></TT> <TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LENGTH</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">OFFSET</FONT> ]
|
|
<DD>Reads <FONT SIZE="-1">LENGTH</FONT> binary bytes from the file into the
|
|
variable at <FONT SIZE="-1">OFFSET</FONT>. Returns number of bytes actually read.
|
|
|
|
<DT><B>seek</B> <FONT SIZE="-1">FILEHANDLE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">POSITION</FONT><TT><B>,</B></TT> <FONT SIZE="-1">WHENCE</FONT>
|
|
<DD>Arbitarily positions the file.
|
|
Returns <B>true</B> if successful.
|
|
|
|
<DT><B>select</B> [ <FONT SIZE="-1">FILEHANDLE</FONT> ]
|
|
<DD>Returns the currently selected filehandle. Sets the
|
|
current default filehandle for output operations if
|
|
<FONT SIZE="-1">FILEHANDLE</FONT> is supplied.
|
|
|
|
<DT><B>select</B> <FONT SIZE="-1">RBITS</FONT><TT><B>,</B></TT> <FONT SIZE="-1">WBITS</FONT><TT><B>,</B></TT> <FONT SIZE="-1">NBITS</FONT><TT><B>,</B></TT> <FONT SIZE="-1">TIMEOUT</FONT>
|
|
<DD>Performs a <I>select</I>(2) system call with the same
|
|
parameters.
|
|
|
|
<DT><B>sprintf</B> <FONT SIZE="-1">FORMAT</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Returns a string formatted by (almost all of) the
|
|
usual <I>printf</I>(3) conventions.
|
|
|
|
<DT><B>sysread</B> <FONT SIZE="-1">FILEHANDLE</FONT><TT><B>,</B></TT> <TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LENGTH</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">OFFSET</FONT> ]
|
|
<DD>Reads <FONT SIZE="-1">LENGTH</FONT> bytes into
|
|
<TT><B>$</B></TT><FONT SIZE="-1">VAR</FONT> at <FONT SIZE="-1">OFFSET</FONT>.
|
|
|
|
<DT><B>syswrite</B> <FONT SIZE="-1">FILEHANDLE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SCALAR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LENGTH</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">OFFSET</FONT> ]
|
|
<DD>Writes <FONT SIZE="-1">LENGTH</FONT> bytes from <FONT SIZE="-1">SCALAR</FONT> at <FONT SIZE="-1">OFFSET</FONT>.
|
|
|
|
<DT><B>tell</B> [ <FONT SIZE="-1">FILEHANDLE</FONT> ]
|
|
<DD>Returns the current file position for the file.
|
|
If <FONT SIZE="-1">FILENAME</FONT> is omitted, assumes the file last read.
|
|
|
|
<DT><B>write</B> [ <FONT SIZE="-1">FILEHANDLE</FONT> ]
|
|
<DD>Writes a formatted record to the specified file, using the format associated
|
|
with that file.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="formats"></A>
|
|
<H2>Formats</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>formline</B> <FONT SIZE="-1">PICTURE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Formats <FONT SIZE="-1">LIST</FONT> according to <FONT SIZE="-1">PICTURE</FONT>
|
|
and accumulates the result into <TT><B>$^A</B></TT>.
|
|
|
|
<DT><B>write</B> [ <FONT SIZE="-1">FILEHANDLE</FONT> ]
|
|
<DD>Writes a formatted record to the specified file, using the format associated
|
|
with that file.
|
|
|
|
</DL>
|
|
|
|
<P>Formats are defined as follows:</P>
|
|
|
|
<UL>
|
|
<B>format</B> [<FONT SIZE="-1">NAME</FONT>] <TT><B>=</B></TT><BR>
|
|
<FONT SIZE="-1">FORMLIST</FONT><BR>
|
|
<TT><B>.</B></TT>
|
|
</UL>
|
|
|
|
<P><FONT SIZE="-1">FORMLIST</FONT> pictures the lines, and contains the arguments which will
|
|
give values to the fields in the lines. <FONT SIZE="-1">NAME</FONT> defaults to
|
|
<TT><B>STDOUT</TT></B> if omitted.</P>
|
|
|
|
<P>Picture fields are:</P>
|
|
|
|
<UL>
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
<TR>
|
|
<TD><TT><B>@<<<</B></TT>...</TD>
|
|
<TD>left adjusted field, repeat the <TT><B><</B></TT> to denote the desired width</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><TT><B>@>>></B></TT>...</TD>
|
|
<TD>right adjusted field</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><TT><B>@|||</B></TT>...</TD>
|
|
<TD>centered field</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><TT><B>@#.##</B></TT>... </TD>
|
|
<TD>numeric format with implied decimal point</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><TT><B>@*</B></TT></TD>
|
|
<TD>a multi-line field</TD>
|
|
</TR>
|
|
</TABLE>
|
|
</UL>
|
|
|
|
Use <TT><B>^</B></TT> instead of <TT><B>@</B></TT> for multiline block filling.<BR>
|
|
Use <TT><B>~</B></TT> at the beginning of a line to suppress unwanted empty lines.<BR>
|
|
Use <TT><B>~~</B></TT> at the beginning of a line to have this format line repeated until
|
|
all fields are exhausted.<BR>
|
|
Use <TT><B>$-</B></TT> to zero to force a page break on the next <B>write</B>.<BR>
|
|
See also <TT><B>$^</B></TT>, <TT><B>$~</B></TT>, <TT><B>$^A</B></TT>, <TT><B>$^F</B></TT>,
|
|
<TT><B>$-</B></TT> and <TT><B>$=</B></TT> in section
|
|
<A HREF="#specialvariables">Special Variables</A>.
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="directory"></A>
|
|
<H2>Directory Reading Routines</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>closedir</B> <FONT SIZE="-1">DIRHANDLE</FONT>
|
|
<DD>Closes a directory opened by <B>opendir</B>.
|
|
|
|
<DT><B>opendir</B> <FONT SIZE="-1">DIRHANDLE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">DIRNAME</FONT>
|
|
<DD>Opens a directory on the handle specified.
|
|
|
|
<DT><B>readdir</B> <FONT SIZE="-1">DIRHANDLE</FONT>
|
|
<DD>Returns the next entry (or an array of entries) from the directory.
|
|
|
|
<DT><B>rewinddir</B> <FONT SIZE="-1">DIRHANDLE</FONT>
|
|
<DD>Positions the directory to the beginning.
|
|
|
|
<DT><B>seekdir</B> <FONT SIZE="-1">DIRHANDLE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">POS</FONT>
|
|
<DD>Sets position for <B>readdir</B> on the directory.
|
|
|
|
<DT><B>telldir</B> <FONT SIZE="-1">DIRHANDLE</FONT>
|
|
<DD>Returns the position in the directory.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="systeminteraction"></A>
|
|
<H2>System Interaction</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>alarm</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Schedules a <TT><B>SIGALRM</B></TT> to be delivered
|
|
after <FONT SIZE="-1">EXPR</FONT> seconds.
|
|
|
|
<DT><B>chdir</B> [ <FONT SIZE="-1">EXPR</FONT> ]
|
|
<DD>Changes the working directory.
|
|
Uses <TT><B>$ENV{"HOME"}</TT></B> or <TT><B>$ENV{"LOGNAME"}</TT></B> if <FONT SIZE="-1">EXPR</FONT> is omitted.
|
|
|
|
<DT><B>chroot</B> <FONT SIZE="-1">FILENAME†</FONT>
|
|
<DD>Changes the root directory for the process and its children.
|
|
|
|
<DT><B>die</B> [ <FONT SIZE="-1">LIST</FONT> ]
|
|
<DD>Prints the value of <FONT SIZE="-1">LIST</FONT> to <TT><B>STDERR</B></TT>
|
|
and exits with the current value of <TT><B>$!</B></TT> (errno).
|
|
If <TT><B>$!</B></TT> is 0, exits with the value of <TT><B>($? >> 8)</B></TT>.
|
|
If <TT><B>($? >> 8)</B></TT> is 0, exits with 255.
|
|
<FONT SIZE="-1">LIST</FONT> defaults to "<TT><B>Died</B></TT>".
|
|
|
|
<DT><B>exec</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Executes the system command in <FONT SIZE="-1">LIST</FONT>; does not return.
|
|
|
|
<DT><B>exit</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Exits immediately with the value of <FONT SIZE="-1">EXPR</FONT>,
|
|
which defaults to <TT><B>0</TT></B> (zero).
|
|
Calls <TT><B>END</TT></B> routines and object destructors before exiting.
|
|
|
|
<DT><B>fork</B>
|
|
<DD>Does a <I>fork</I>(2) system call.
|
|
Returns the process ID of the child to the parent process and zero to the child process.
|
|
|
|
<DT><B>getlogin</B>
|
|
<DD>Returns the current login name as known by the system.
|
|
|
|
<DT><B>getpgrp</B> [ <FONT SIZE="-1">PID</FONT> ]
|
|
<DD>Returns the process group for process <FONT SIZE="-1">PID</FONT>
|
|
(0, or omitted, means the current process).
|
|
|
|
<DT><B>getppid</B>
|
|
<DD>Returns the process ID of the parent process.
|
|
|
|
<DT><B>getpriority</B> <FONT SIZE="-1">WHICH</FONT><TT><B>,</B></TT> <FONT SIZE="-1">WHO</FONT>
|
|
<DD>Returns the current priority for a process, process group, or user.
|
|
|
|
<DT><B>glob</B> <FONT SIZE="-1">PAT</FONT>
|
|
<DD>Returns a list of filenames that match the shell pattern <FONT SIZE="-1">PAT</FONT>.
|
|
|
|
<DT><B>kill</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Sends a signal to a list of processes.
|
|
The first element of the list must be the signal to send
|
|
(either numeric, or its name as a string).
|
|
|
|
<DT><B>setpgrp</B> <FONT SIZE="-1">PID</FONT><TT><B>,</B></TT> <FONT SIZE="-1">PGRP</FONT>
|
|
<DD>Sets the process group for the <FONT SIZE="-1">PID</FONT> (0 means the current process).
|
|
|
|
<DT><B>setpriority</B> <FONT SIZE="-1">WHICH</FONT><TT><B>,</B></TT> <FONT SIZE="-1">WHO</FONT><TT><B>,</B></TT> <FONT SIZE="-1">PRIORITY</FONT>
|
|
<DD>Sets the current priority for a process, process group, or a user.
|
|
|
|
<DT><B>sleep</B> [ <FONT SIZE="-1">EXPR</FONT> ]
|
|
<DD>Causes the program to sleep for <FONT SIZE="-1">EXPR</FONT> seconds,
|
|
or forever if no <FONT SIZE="-1">EXPR</FONT>.
|
|
Returns the number of seconds actually slept.
|
|
|
|
<DT><B>syscall</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Calls the system call specified in the first element of the list, passing the
|
|
rest of the list as arguments to the call.
|
|
|
|
<DT><B>system</B> <FONT SIZE="-1">LIST</FONT>
|
|
<DD>Does exactly the same thing as <B>exec</B> <FONT SIZE="-1">LIST</FONT>
|
|
except that a fork is performed first,
|
|
and the parent process waits for the child process to complete.
|
|
|
|
<DT><B>times</B>
|
|
<DD>Returns a 4-element array
|
|
(0: <TT><B>$</B></TT>user,
|
|
1: <TT><B>$</B></TT>system,
|
|
2: <TT><B>$</B></TT>cursor,
|
|
3: <TT><B>$</B></TT>csystem)
|
|
giving the user and system times, in seconds, for this process
|
|
and the children of this process.
|
|
|
|
<DT><B>umask</B> [ <FONT SIZE="-1">EXPR</FONT> ]
|
|
<DD>Sets the umask for the process and returns the old one.
|
|
If <FONT SIZE="-1">EXPR</FONT> is omitted, returns current umask value.
|
|
|
|
<DT><B>wait</B>
|
|
<DD>Waits for a child process to terminate and returns the process ID of the
|
|
deceased process (-1 if none). The status is returned in <TT><B>$?</B></TT>.
|
|
|
|
<DT><B>waitpid</B> <FONT SIZE="-1">PID</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FLAGS</FONT>
|
|
<DD>Performs the same function as the corresponding system call.
|
|
|
|
<DT><B>warn</B> [ <FONT SIZE="-1">LIST</FONT> ]
|
|
<DD>Prints the message on <TT><B>STDERR</B></TT> like <B>die</B>, but doesn't exit.
|
|
<FONT SIZE="-1">LIST</FONT> defaults to "<TT><B>Warning: something's wrong</TT></B>".
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="networking"></A>
|
|
<H2>Networking</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>accept</B> <FONT SIZE="-1">NEWSOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">GENERICSOCKET</FONT>
|
|
<DD>Accepts a new socket.
|
|
|
|
<DT><B>bind</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">NAME</FONT>
|
|
<DD>Binds the <FONT SIZE="-1">NAME</FONT> to the <FONT SIZE="-1">SOCKET</FONT>.
|
|
|
|
<DT><B>connect</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">NAME</FONT>
|
|
<DD>Connects the <FONT SIZE="-1">NAME</FONT> to the <FONT SIZE="-1">SOCKET</FONT>.
|
|
|
|
<DT><B>getpeername</B> <FONT SIZE="-1">SOCKET</FONT>
|
|
<DD>Returns the socket address of the other end of the <FONT SIZE="-1">SOCKET</FONT>.
|
|
|
|
<DT><B>getsockname</B> <FONT SIZE="-1">SOCKET</FONT>
|
|
<DD>Returns the name of the <FONT SIZE="-1">SOCKET</FONT>.
|
|
|
|
<DT><B>getsockopt</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LEVEL</FONT><TT><B>,</B></TT> <FONT SIZE="-1">OPTNAME</FONT>
|
|
<DD>Returns the socket options.
|
|
|
|
<DT><B>listen</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">QUEUESIZE</FONT>
|
|
<DD>Starts listening on the specified <FONT SIZE="-1">SOCKET</FONT>.
|
|
|
|
<DT><B>recv</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SCALAR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LENGTH</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FLAGS</FONT>
|
|
<DD>Receives a message on <FONT SIZE="-1">SOCKET</FONT>.
|
|
|
|
<DT><B>send</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">MSG</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FLAGS</FONT> [ <TT><B>,</B></TT> <FONT SIZE="-1">TO</FONT> ]
|
|
<DD>Sends a message on the <FONT SIZE="-1">SOCKET</FONT>.
|
|
|
|
<DT><B>setsockopt</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">LEVEL</FONT><TT><B>,</B></TT> <FONT SIZE="-1">OPTNAME</FONT><TT><B>,</B></TT> <FONT SIZE="-1">OPTVAL</FONT>
|
|
<DD>Sets the requested socket option.
|
|
|
|
<DT><B>shutdown</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">HOW</FONT>
|
|
<DD>Shuts down a <FONT SIZE="-1">SOCKET</FONT>.
|
|
|
|
<DT><B>socket</B> <FONT SIZE="-1">SOCKET</FONT><TT><B>,</B></TT> <FONT SIZE="-1">DOMAIN</FONT><TT><B>,</B></TT> <FONT SIZE="-1">TYPE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">PROTOCOL</FONT>
|
|
<DD>Creates a <FONT SIZE="-1">SOCKET</FONT> in <FONT SIZE="-1">DOMAIN</FONT> with <FONT SIZE="-1">TYPE</FONT> and <FONT SIZE="-1">PROTOCOL</FONT>.
|
|
|
|
<DT><B>socketpair</B> <FONT SIZE="-1">SOCKET1</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SOCKET2</FONT><TT><B>,</B></TT> <FONT SIZE="-1">DOMAIN</FONT><TT><B>,</B></TT> <FONT SIZE="-1">TYPE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">PROTOCOL</FONT>
|
|
<DD>Works the same as <B>socket</B>, but creates a pair of bidirectional sockets.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="systemv"></A>
|
|
<H2>System V IPC</H2>
|
|
|
|
<P>You need to<TT><B> require "sys/ipc.ph" </TT></B>before you can use the
|
|
symbolic names of the operations.</P>
|
|
|
|
<DL>
|
|
|
|
<DT><B>msgctl</B> <FONT SIZE="-1">ID</FONT><TT><B>,</B></TT> <FONT SIZE="-1">CMD</FONT><TT><B>,</B></TT> <FONT SIZE="-1">ARGS</FONT>
|
|
<DD>Calls <I>msgctl</I>(2). If <FONT SIZE="-1">CMD</FONT> is <TT><B>&IPC_STAT</TT></B> then <FONT SIZE="-1">ARGS</FONT> must
|
|
be a variable.
|
|
|
|
<DT><B>msgget</B> <FONT SIZE="-1">KEY</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FLAGS</FONT>
|
|
<DD>Creates a message queue for <FONT SIZE="-1">KEY</FONT>.
|
|
Returns the message queue identifier.
|
|
|
|
<DT><B>msgsnd</B> <FONT SIZE="-1">ID</FONT><TT><B>,</B></TT> <FONT SIZE="-1">MSG</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FLAGS</FONT>
|
|
<DD>Sends <FONT SIZE="-1">MSG</FONT> to queue <FONT SIZE="-1">ID</FONT>.
|
|
|
|
<DT><B>msgrcv</B> <FONT SIZE="-1">ID</FONT><TT><B>,</B></TT> <TT><B>$</TT></B><FONT SIZE="-1">VAR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SIZE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">TYPE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FLAGS</FONT>
|
|
<DD>Receives a message from queue <FONT SIZE="-1">ID</FONT> into <FONT SIZE="-1">VAR</FONT>.
|
|
|
|
<DT><B>semctl</B> <FONT SIZE="-1">ID</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SEMNUM</FONT><TT><B>,</B></TT> <FONT SIZE="-1">CMD</FONT><TT><B>,</B></TT> <FONT SIZE="-1">ARG</FONT>
|
|
<DD>Calls <I>semctl</I>(2).
|
|
If <FONT SIZE="-1">CMD</FONT> is <TT><B>&IPC_STAT</TT></B> of <TT><B>&GETALL</TT></B>
|
|
then <FONT SIZE="-1">ARG</FONT> must be a variable.
|
|
|
|
<DT><B>semget</B> <FONT SIZE="-1">KEY</FONT><TT><B>,</B></TT> <FONT SIZE="-1">NSEMS</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SIZE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FLAGS</FONT>
|
|
<DD>Creates a set of semaphores for <FONT SIZE="-1">KEY</FONT>.
|
|
Returns the message semaphore identifier.
|
|
|
|
<DT><B>semop</B> <FONT SIZE="-1">KEY</FONT><TT><B>,</B></TT> ...
|
|
<DD>Performs semaphore operations.
|
|
|
|
<DT><B>shmctl</B> <FONT SIZE="-1">ID</FONT><TT><B>,</B></TT> <FONT SIZE="-1">CMD</FONT><TT><B>,</B></TT> <FONT SIZE="-1">ARG</FONT>
|
|
<DD>Calls <I>shmctl</I>(2).
|
|
If <FONT SIZE="-1">CMD</FONT> is <TT><B>&IPC_STAT</TT></B>
|
|
then <FONT SIZE="-1">ARG</FONT> must be a variable.
|
|
|
|
<DT><B>shmget</B> <FONT SIZE="-1">KEY</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SIZE</FONT><TT><B>,</B></TT> <FONT SIZE="-1">FLAGS</FONT>
|
|
<DD>Creates shared memory.
|
|
Returns the shared memory segment identifier.
|
|
|
|
<DT><B>shmread</B> <FONT SIZE="-1">ID</FONT><TT><B>,</B></TT> <TT><B>$</TT></B><FONT SIZE="-1">VAR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">POS</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SIZE</FONT>
|
|
<DD>Reads at most <FONT SIZE="-1">SIZE</FONT> bytes of the contents of shared
|
|
memory segment <FONT SIZE="-1">ID</FONT> starting at offset <FONT SIZE="-1">POS</FONT> into <FONT SIZE="-1">VAR</FONT>.
|
|
|
|
<DT><B>shmwrite</B> <FONT SIZE="-1">ID</FONT><TT><B>,</B></TT> <FONT SIZE="-1">STRING</FONT><TT><B>,</B></TT> <FONT SIZE="-1">POS</FONT><TT><B>,</B></TT> <FONT SIZE="-1">SIZE</FONT>
|
|
<DD>Writes at most <FONT SIZE="-1">SIZE</FONT> bytes of <FONT SIZE="-1">STRING</FONT> into the contents of
|
|
shared memory segment <FONT SIZE="-1">ID</FONT> at offset <FONT SIZE="-1">POS</FONT>.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="miscellaneous"></A>
|
|
<H2>Miscellaneous</H2>
|
|
|
|
<DL>
|
|
|
|
<DT><B>defined</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Tests whether the lvalue <FONT SIZE="-1">EXPR</FONT> has an actual value.
|
|
|
|
<DT><B>do</B> <FONT SIZE="-1">FILENAME</FONT>
|
|
<DD>Executes <FONT SIZE="-1">FILENAME</FONT> as a Perl script.
|
|
See also <B>require</B> in the section
|
|
<A HREF="#subroutines">Subroutines, Packages and Modules</A>.
|
|
|
|
<DT><B>dump</B> [ <FONT SIZE="-1">LABEL</FONT> ]
|
|
<DD>Immediate core dump.
|
|
When reincarnated, starts at <FONT SIZE="-1">LABEL</FONT>.
|
|
|
|
<DT><B>eval</B> <TT><B>{</TT></B> <FONT SIZE="-1">EXPR</FONT> <TT><B>;</TT></B> ... <TT><B>}</TT></B>
|
|
<DD>Executes the code between <TT><B>{</TT></B> and <TT><B>}</TT></B>.
|
|
Traps runtime errors as described
|
|
with <B>eval</B><TT><B>(</TT></B><FONT SIZE="-1">EXPR</FONT><TT><B>)</TT></B>, in the section <A HREF="#string">String Functions</A>.
|
|
|
|
<DT><B>local</B> <FONT SIZE="-1">VARIABLE</FONT>
|
|
<DT><B>local</B> <TT><B>(</TT></B> <FONT SIZE="-1">LIST</FONT> <TT><B>)</TT></B>
|
|
<DD>Creates a scope for the listed variables local to the enclosing block,
|
|
subroutine or <B>eval</B>.
|
|
|
|
<DT><B>my</B> <FONT SIZE="-1">VARIABLE</FONT>
|
|
<DT><B>my</B> <TT><B>(</TT></B> <FONT SIZE="-1">LIST</FONT> <TT><B>)</TT></B>
|
|
<DD>Creates a scope for the listed variables lexically local to the enclosing block,
|
|
subroutine or <B>eval</B>.
|
|
|
|
<DT><B>ref</B> <FONT SIZE="-1">EXPR†</FONT>
|
|
<DD>Returns a <B>true</B> value if <FONT SIZE="-1">EXPR</FONT> is a reference.
|
|
Returns the package name if <FONT SIZE="-1">EXPR</FONT> has been blessed into a package.
|
|
|
|
<DT><B>reset</B> [ <FONT SIZE="-1">EXPR</FONT> ]
|
|
<DD>Resets <TT><B>??</B></TT> searches so that they work again.
|
|
<FONT SIZE="-1">EXPR</FONT> is a list of single letters. All variables and arrays
|
|
beginning with one of those letters are reset
|
|
to their pristine state. Only affects the current package.
|
|
|
|
<DT><B>scalar</B> <FONT SIZE="-1">EXPR</FONT>
|
|
<DD>Forces evaluation of <FONT SIZE="-1">EXPR</FONT> in scalar context.
|
|
|
|
<DT><B>undef</B> [ <FONT SIZE="-1">LVALUE</FONT> ]
|
|
<DD>Undefines the <FONT SIZE="-1">LVALUE</FONT>. Always returns the undefined value.
|
|
|
|
<DT><B>wantarray</B>
|
|
<DD>Returns <B>true</B> if the current context expects an array value.
|
|
|
|
</DL>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="information"></A>
|
|
<H2>Information from System Files</H2>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2><LI><FONT SIZE="+1"><B>passwd</B></FONT></TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2>Returns <TT><B>($</B></TT>name, <TT><B>$</B></TT>passwd,
|
|
<TT><B>$</B></TT>uid, <TT><B>$</B></TT>gid, <TT><B>$</B></TT>quota,
|
|
<TT><B>$</B></TT>comment, <TT><B>$</B></TT>gcos, <TT><B>$</B></TT>dir,
|
|
<TT><B>$</B></TT>shell<TT><B>)</TT></B>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>endpwent</B></TD>
|
|
<TD>Ends lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getpwend</B></TD>
|
|
<TD>Gets next user information.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getpwnam</B> <FONT SIZE="-1">NAME</FONT></TD>
|
|
<TD>Gets information by name.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getpwuid</B> <FONT SIZE="-1">UID</FONT></TD>
|
|
<TD>Gets information by user ID.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>setpwent</B></TD>
|
|
<TD>Resets lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR><TD COLSPAN=2> </TD></TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2><LI><FONT SIZE="+1"><B>group</B></FONT></TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2>Returns <TT><B>($</B></TT>name, <TT><B>$</B></TT>passwd,
|
|
<TT><B>$</B></TT>gid, <TT><B>$</B></TT>members<TT><B>)</TT></B>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>endgrent</B></TD>
|
|
<TD>Ends lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getgrgid</B> <FONT SIZE="-1">GID</FONT></TD>
|
|
<TD>Gets information by group ID.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getgrnam</B> <FONT SIZE="-1">NAME</FONT></TD>
|
|
<TD>Gets information by name.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getgrent</B></TD>
|
|
<TD>Gets next information.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>setgrent</B></TD>
|
|
<TD>Resets lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR><TD COLSPAN=2> </TD></TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2><LI><FONT SIZE="+1"><B>hosts</B></FONT></TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2>Returns <TT><B>($</B></TT>name, <TT><B>$</B></TT>aliases,
|
|
<TT><B>$</B></TT>addrtype, <TT><B>$</B></TT>length, <TT><B>@</B></TT>addrs<TT><B>)</TT></B>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>endhostent</B></TD>
|
|
<TD>Ends lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>gethostbyaddr</B> <FONT SIZE="-1">ADDR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">ADDRTYPE</FONT></TD>
|
|
<TD>Gets information by IP address.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>gethostbyname</B> <FONT SIZE="-1">NAME</FONT></TD>
|
|
<TD>Gets information by hostname.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>gethostent</B></TD>
|
|
<TD>Gets next host information.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>sethostent</B> <FONT SIZE="-1">STAYOPEN</FONT></TD>
|
|
<TD>Resets lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR><TD COLSPAN=2> </TD></TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2><LI><FONT SIZE="+1"><B>networks</B></FONT></TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2>Returns <TT><B>($</B></TT>name, <TT><B>$</B></TT>aliases,
|
|
<TT><B>$</B></TT>addrtype, <TT><B>$</B></TT>net<TT><B>)</TT></B>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>endnetent</B></TD>
|
|
<TD>Ends lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getnetbyaddr</B> <FONT SIZE="-1">ADDR</FONT><TT><B>,</B></TT> <FONT SIZE="-1">TYPE</FONT></TD>
|
|
<TD>Gets information by address and type.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getnetbyname</B> <FONT SIZE="-1">NAME</FONT></TD>
|
|
<TD>Gets information by network name.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getnetent</B></TD>
|
|
<TD>Gets next network information.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>setnetent</B> <FONT SIZE="-1">STAYOPEN</FONT></TD>
|
|
<TD>Resets lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR><TD COLSPAN=2> </TD></TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2><LI><FONT SIZE="+1"><B>services</B></FONT></TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2>Returns <TT><B>($</B></TT>name, <TT><B>$</B></TT>aliases,
|
|
<TT><B>$</B></TT>port, <TT><B>$</B></TT>proto<TT><B>)</TT></B>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>endservent</B></TD>
|
|
<TD>Ends lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getservbyname</B> <FONT SIZE="-1">NAME</FONT><TT><B>,</B></TT> <FONT SIZE="-1">PROTO</FONT></TD>
|
|
<TD>Gets information by service name.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getservbyport</B> <FONT SIZE="-1">PORT</FONT><TT><B>,</B></TT> <FONT SIZE="-1">PROTO</FONT></TD>
|
|
<TD>Gets information by service port.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getservent</B></TD>
|
|
<TD>Gets next service information.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>setservent</B> <FONT SIZE="-1">STAYOPEN</FONT></TD>
|
|
<TD>Resets lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR><TD COLSPAN=2> </TD></TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2><LI><FONT SIZE="+1"><B>protocols</B></FONT></TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD COLSPAN=2>Returns <TT><B>($</B></TT>name, <TT><B>$</B></TT>aliases,
|
|
<TT><B>$</B></TT>proto<TT><B>)</TT></B>.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>endprotoent</B></TD>
|
|
<TD>Ends lookup processing.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getprotobyname</B> <FONT SIZE="-1">NAME</FONT></TD>
|
|
<TD>Gets information by protocol name.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getprotobynumber</B> <FONT SIZE="-1">NUMBER</FONT></TD>
|
|
<TD>Gets information by protocol number.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>getprotoent</B></TD>
|
|
<TD>Gets next protocol information.</TD>
|
|
</TR>
|
|
|
|
<TR>
|
|
<TD><B>setprotoent</B> <FONT SIZE="-1">STAYOPEN</FONT></TD>
|
|
<TD>Resets lookup processing.</TD>
|
|
</TR>
|
|
|
|
</TABLE>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="specialvariables"></A>
|
|
<H2>Special Variables</H2>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR><TD VALIGN=top COLSPAN=2>The following variables are global and should be
|
|
localized in subroutines:</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$_</B></TT></TD>
|
|
<TD VALIGN=top>The default input and pattern-searching space.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$.</B></TT></TD>
|
|
<TD VALIGN=top>The current input line number of the last filehandle that was read.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$/</B></TT></TD>
|
|
<TD VALIGN=top>The input record separator, newline by default. May be multicharacter.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$,</B></TT></TD>
|
|
<TD VALIGN=top>The output field separator for the print operator.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$"</B></TT></TD>
|
|
<TD VALIGN=top>The separator that joins elements of arrays interpolated in strings.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$\</B></TT></TD>
|
|
<TD VALIGN=top>The output record separator for the print operator.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$#</B></TT></TD>
|
|
<TD VALIGN=top>The output format for printed numbers. Depreciated.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$*</B></TT></TD>
|
|
<TD VALIGN=top>Set to 1 to do multiline matching within strings.
|
|
Deprecated, see the <B>m</B> and <B>s</B> modifiers in section
|
|
<A HREF="#search">Search and Replace Functions</A>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$?</B></TT></TD>
|
|
<TD VALIGN=top>The status returned by the last <TT><B>`</B></TT>...<TT><B>`</B></TT> command,
|
|
pipe <B>close</B> or <B>system</B> operator.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$]</B></TT></TD>
|
|
<TD VALIGN=top>The perl version number, e.g., <TT><B>5.001</TT></B>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$[</B></TT></TD>
|
|
<TD VALIGN=top>The index of the first element in an array, and of the first character
|
|
in a substring. Default is 0. Depreciated.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$;</B></TT></TD>
|
|
<TD VALIGN=top>The subscript separator for multidimensional array emulation.
|
|
Default is "<TT><B>\034</B></TT>".</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$!</B></TT></TD>
|
|
<TD VALIGN=top>If used in a numeric context, yields the current value of <B>errno</B>.
|
|
If used in a string context, yields the corresponding error string.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$@</B></TT></TD>
|
|
<TD VALIGN=top>The Perl error message from the last <B>eval</B> or <B>do</B> <FONT SIZE="-1">EXPR</FONT>
|
|
command.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$:</B></TT></TD>
|
|
<TD VALIGN=top>The set of characters after which a string may be broken to
|
|
fill continuation fields (starting with <TT><B>^</B></TT>) in a format.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$0</B></TT></TD>
|
|
<TD VALIGN=top>The name of the file containing the Perl script being executed.
|
|
May be assigned to.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$$</B></TT></TD>
|
|
<TD VALIGN=top>The process ID of the currently executing Perl program.
|
|
Altered (in the child process) by <B>fork</B>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$<</B></TT></TD>
|
|
<TD VALIGN=top>The real user ID of this process.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$></B></TT></TD>
|
|
<TD VALIGN=top>The effective user ID of this process.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$(</B></TT></TD>
|
|
<TD VALIGN=top>The real group ID of this process.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$)</B></TT></TD>
|
|
<TD VALIGN=top>The effective group ID of this process.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^A</B></TT></TD>
|
|
<TD VALIGN=top>The accumulator for <B>formline</B> and <B>write</B> operations.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^D</B></TT></TD>
|
|
<TD VALIGN=top>The debug flags as passed to perl using <TT><B>-D</B></TT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^F</B></TT></TD>
|
|
<TD VALIGN=top>The highest system file descriptor, ordinarily 2.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^I</B></TT></TD>
|
|
<TD VALIGN=top>In-place edit extension as passed to Perl using <TT><B>-i</B></TT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^L</B></TT></TD>
|
|
<TD VALIGN=top>Formfeed character used in formats.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^P</B></TT></TD>
|
|
<TD VALIGN=top>Internal debugging flag.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^T</B></TT></TD>
|
|
<TD VALIGN=top>The time (as delivered by <B>time</B>) when the program started.
|
|
This value is used by the file test operators <TT><B>-M</B></TT>,
|
|
<TT><B>-A</B></TT> and <TT><B>-C</B></TT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^W</B></TT></TD>
|
|
<TD VALIGN=top>The value if the <TT><B>-w</B></TT> option as passed to Perl.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^X</B></TT></TD>
|
|
<TD VALIGN=top>The name by which the currently executing program was invoked.</TD></TR>
|
|
|
|
<TR><TD COLSPAN=2> </TD></TR>
|
|
<TR><TD VALIGN=top COLSPAN=2>The following variables are context dependent
|
|
and need not be localized:</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$%</B></TT></TD>
|
|
<TD VALIGN=top>The current page number of the currently selected output channel.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$=</B></TT></TD>
|
|
<TD VALIGN=top>The page length of the current output channel. Default is 60 lines.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$-</B></TT></TD>
|
|
<TD VALIGN=top>The number of lines remaining on the page.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$~</B></TT></TD>
|
|
<TD VALIGN=top>The name of the current report format.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$^</B></TT></TD>
|
|
<TD VALIGN=top>The name of the current top-of-page format.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$|</B></TT></TD>
|
|
<TD VALIGN=top>If set to nonzero, forces a flush after every write or print on the
|
|
currently selected output channel. Default is 0.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$ARGV</B></TT></TD>
|
|
<TD VALIGN=top>The name of the current file when reading from <TT><B><></B></TT>.</TD></TR>
|
|
|
|
<TR><TD COLSPAN=2> </TD></TR>
|
|
<TR><TD VALIGN=top COLSPAN=2>The following variables are always local to the
|
|
current block:</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$&</B></TT></TD>
|
|
<TD VALIGN=top>The string matched by the last successful pattern match.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$`</B></TT></TD>
|
|
<TD VALIGN=top>The string preceding what was matched by the last successful match.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$'</B></TT></TD>
|
|
<TD VALIGN=top>The string following what was matched by the last successful match.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$+</B></TT></TD>
|
|
<TD VALIGN=top>The last bracket matched by the last search pattern.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>$1</B></TT>...<TT><B>$9</B></TT>... </TD>
|
|
<TD VALIGN=top>Contain the subpatterns from the corresponding sets of parentheses in the
|
|
last pattern successfully matched. <TT><B>$10</B></TT>... and up are only available if the
|
|
match contained that many subpatterns.</TD></TR>
|
|
|
|
</TABLE>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="specialarrays"></A>
|
|
<H2>Special Arrays</H2>
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR><TD VALIGN=top><TT><B>@ARGV</B></TT></TD>
|
|
<TD VALIGN=top>Contains the command-line arguments for the script (not including the
|
|
command name).</TD></TR>
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<TR><TD VALIGN=top><TT><B>@EXPORT</B></TT></TD>
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<TD VALIGN=top>Names the methods a package exports by default.</TD></TR>
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<TR><TD VALIGN=top><TT><B>@EXPORT_OK </B></TT></TD>
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<TD VALIGN=top>Names the methods a package can export upon explicit request.</TD></TR>
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<TR><TD VALIGN=top><TT><B>@INC</B></TT></TD>
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<TD VALIGN=top>Contains the list of places to look for Perl scripts to be evaluated by
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the <B>do</B> <FONT SIZE="-1">FILENAME</FONT> and <B>require</B> commands.</TD></TR>
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<TR><TD VALIGN=top><TT><B>@ISA</B></TT></TD>
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<TD VALIGN=top>List of base classes of a package.</TD></TR>
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<TR><TD VALIGN=top><TT><B>@_</B></TT></TD>
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<TD VALIGN=top>Parameter array for subroutines. Also used by <B>split</B>
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if not in array context.</TD></TR>
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<TR><TD VALIGN=top><TT><B>%ENV</B></TT></TD>
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<TD VALIGN=top>Contains the current environment.</TD></TR>
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<TR><TD VALIGN=top><TT><B>%INC</B></TT></TD>
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<TD VALIGN=top>List of files that have been included with <B>require</B> or <B>do</B>.</TD></TR>
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<TR><TD VALIGN=top><TT><B>%OVERLOAD</B></TT></TD>
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<TD VALIGN=top>Can be used to overload operators in a package.</TD></TR>
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<TR><TD VALIGN=top><TT><B>%SIG</B></TT></TD>
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<TD VALIGN=top>Used to set signal handlers for various signals.</TD></TR>
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</TABLE>
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<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
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<!-- ----------------------------------------------------------------------------- -->
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<A NAME="environment"></A>
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<H2>Environment Variables</H2>
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<P>Perl uses the following environment variables.</P>
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<TABLE CELLSPACING=0 CELLPADDING=0>
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<TR><TD VALIGN=top><TT><B>HOME</B></TT></TD>
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<TD VALIGN=top>Used if <B>chdir</B> has no argument.</TD></TR>
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<TR><TD VALIGN=top><TT><B>LOGDIR</B></TT></TD>
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<TD VALIGN=top>Used if <B>chdir</B> has no argument and <TT><B>HOME</TT></B> is not set.</TD></TR>
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<TR><TD VALIGN=top><TT><B>PATH</B></TT></TD>
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<TD VALIGN=top>Used in executing subprocesses, and in finding the Perl script if <TT><B>-S</TT></B>
|
|
is used.</TD></TR>
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<TR><TD VALIGN=top><TT><B>PERL5LIB </B></TT></TD>
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<TD VALIGN=top>A colon-separated list of directories to look in for Perl library files
|
|
before looking in the standard library and the current directory.</TD></TR>
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<TR><TD VALIGN=top><TT><B>PERL5DB</B></TT></TD>
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<TD VALIGN=top>The command to get the debugger code.
|
|
<BR>Defaults to <TT><B>BEGIN { require 'perl5db.pl' }</TT></B>.</TD></TR>
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<TR><TD VALIGN=top><TT><B>PERLLIB</B></TT></TD>
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<TD VALIGN=top>Used instead of <TT><B>PERL5LIB</TT></B> if the latter is not defined.</TD></TR>
|
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</TABLE>
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|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<A NAME="debugger"></A>
|
|
<H2>The Perl Debugger</H2>
|
|
|
|
The Perl symbolic debugger is invoked with <TT><B>perl -d</B></TT>.
|
|
|
|
<TABLE CELLSPACING=0 CELLPADDING=0>
|
|
|
|
<TR><TD VALIGN=top><TT><B>h</B></TT></TD>
|
|
<TD VALIGN=top>Prints out a help message.</TD></TR>
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|
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<TR><TD VALIGN=top><TT><B>T</B></TT></TD>
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|
<TD VALIGN=top>Prints a stack trace.</TD></TR>
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|
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|
<TR><TD VALIGN=top><TT><B>s</B></TT></TD>
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|
<TD VALIGN=top>Single steps.</TD></TR>
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|
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<TR><TD VALIGN=top><TT><B>n</B></TT></TD>
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|
<TD VALIGN=top>Single steps around subroutine call.</TD></TR>
|
|
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|
<TR><TD VALIGN=top><FONT SIZE="-1">RETURN key</FONT></TD>
|
|
<TD VALIGN=top>Repeats last <TT><B>s</B></TT> or <TT><B>n</B></TT>.</TD></TR>
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|
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<TR><TD VALIGN=top><TT><B>r</B></TT></TD>
|
|
<TD VALIGN=top>Returns form the current subroutine.</TD></TR>
|
|
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|
<TR><TD VALIGN=top><TT><B>c</B></TT> [ <FONT SIZE="-1">LINE</FONT> ]</TD>
|
|
<TD VALIGN=top>Continues (until <FONT SIZE="-1">LINE</FONT>,
|
|
or another breakpoint, or exit).</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>p</B></TT> <FONT SIZE="-1">EXPR</FONT></TD>
|
|
<TD VALIGN=top>Prints <FONT SIZE="-1">EXPR</FONT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>l</B></TT> [ <FONT SIZE="-1">RANGE</FONT> ]</TD>
|
|
<TD VALIGN=top>Lists a range of lines.
|
|
<FONT SIZE="-1">RANGE</FONT> may be a number, start-end,
|
|
start+amount, or a subroutine name. If <FONT SIZE="-1">RANGE</FONT> is omitted,
|
|
lists next window.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>w</B></TT></TD>
|
|
<TD VALIGN=top>Lists window around current line.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>-</B></TT></TD>
|
|
<TD VALIGN=top>Lists previous window.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>f</B></TT> <FONT SIZE="-1">FILE</FONT></TD>
|
|
<TD VALIGN=top>Switches to <FONT SIZE="-1">FILE</FONT> and starts listing it.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>l</B></TT> <FONT SIZE="-1">SUB</FONT></TD>
|
|
<TD VALIGN=top>Lists the named subroutine.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>S</B></TT></TD>
|
|
<TD VALIGN=top>List the names of all subroutines.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>/</B></TT><FONT SIZE="-1">PATTERN</FONT><TT><B>/</B></TT></TD>
|
|
<TD VALIGN=top>Searches forward for <FONT SIZE="-1">PATTERN</FONT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>?</B></TT><FONT SIZE="-1">PATTERN</FONT><TT><B>?</B></TT></TD>
|
|
<TD VALIGN=top>Searches backward for <FONT SIZE="-1">PATTERN</FONT>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top NOWRAP><TT><B>b</B></TT> [ <FONT SIZE="-1">LINE</FONT> [ <FONT SIZE="-1">CONDITION</FONT> ] ] </TD>
|
|
<TD VALIGN=top>Sets breakpoint at <FONT SIZE="-1">LINE</FONT>; default is the current line.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>b</B></TT> <FONT SIZE="-1">SUB</FONT> [ <FONT SIZE="-1">CONDITION</FONT> ]</TD>
|
|
<TD VALIGN=top>Sets breakpoint at the subroutine.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>d</B></TT> [ <FONT SIZE="-1">LINE</FONT> ]</TD>
|
|
<TD VALIGN=top>Deletes breakpoint at the given line.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>D</B></TT></TD>
|
|
<TD VALIGN=top>Deletes all breakpoints.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>L</B></TT></TD>
|
|
<TD VALIGN=top>Lists lines that have breakpoints or actions.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>a</B></TT> <FONT SIZE="-1">LINE COMMAND</FONT></TD>
|
|
<TD VALIGN=top>Sets an action for line.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>A</B></TT></TD>
|
|
<TD VALIGN=top>Deletes all line actions.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B><</B></TT> <FONT SIZE="-1">COMMAND</FONT></TD>
|
|
<TD VALIGN=top>Sets an action to be executed before every debugger prompt.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>></B></TT> <FONT SIZE="-1">COMMAND</FONT></TD>
|
|
<TD VALIGN=top>Sets an action to be executed before every
|
|
<TT><B>s</B></TT>, <TT><B>c</B></TT> or <TT><B>n</B></TT> command.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top NOWRAP><TT><B>V</B></TT> [ <FONT SIZE="-1">PACKAGE</FONT> [ <FONT SIZE="-1">VARS</FONT> ] ] </TD>
|
|
<TD VALIGN=top>Lists all variables in a package. Default package is <TT><B>main</TT></B>.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>X</B></TT> [ <FONT SIZE="-1">VARS</FONT> ]</TD>
|
|
<TD VALIGN=top>Like <TT><B>V</B></TT>, but assumes current package.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>!</B></TT> [ [<TT><B>-</TT></B>]<FONT SIZE="-1">NUMBER</FONT> ]</TD>
|
|
<TD VALIGN=top>Re-executes a command. Default is the previous command.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>H</B></TT> [ -<FONT SIZE="-1">NUMBER</FONT> ]</TD>
|
|
<TD VALIGN=top>Displays the last <TT><B>-</TT></B><FONT SIZE="-1">NUMBER</FONT>
|
|
commands of more than one letter.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>t</B></TT></TD>
|
|
<TD VALIGN=top>Toggles trace mode.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>=</B></TT> [ <FONT SIZE="-1">ALIAS VALUE</FONT> ]</TD>
|
|
<TD VALIGN=top>Sets alias, or lists current aliases.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><TT><B>q</B></TT></TD>
|
|
<TD VALIGN=top>Quits. You may also use your <FONT SIZE="-1">EOF key</FONT> character.</TD></TR>
|
|
|
|
<TR><TD VALIGN=top><FONT SIZE="-1">COMMAND</FONT></TD>
|
|
<TD VALIGN=top>Executes <FONT SIZE="-1">COMMAND</FONT> as a Perl statement.</TD></TR>
|
|
|
|
</TABLE>
|
|
|
|
<H4 ALIGN=center>Back to <A HREF="#contents">Contents</A> or <A HREF="#index">Index</A></H4>
|
|
|
|
<!-- ----------------------------------------------------------------------------- -->
|
|
|
|
<HR NOSHADE SIZE=4>
|
|
|
|
<H3>Other Summaries and Demos</H3>
|
|
<UL>
|
|
<LI>See my <A HREF="http://www.pcnet.com/~rhswain/">home page</A> for other summaries and demos:
|
|
APL, REXX, XEDIT, Perl, HTML, RGB Colors, HTTP Cookies, Email Forms,
|
|
CGI Environment Variables, Server Side Includes, etc...
|
|
</UL>
|
|
|
|
<HR SIZE=1>
|
|
|
|
<CENTER>
|
|
|
|
<ADDRESS>
|
|
Text copyright © 1996 Johan Vromans<BR>
|
|
HTML copyright © 1996-1997 Rex Swain<BR>
|
|
Email <A HREF="mailto:[email protected]">[email protected]</A>,
|
|
Web <A HREF="http://www.pcnet.com/~rhswain/">http://www.pcnet.com/~rhswain</A><BR>
|
|
Permission granted to distribute unmodified copies<BR>
|
|
Reports of errors or omissions appreciated
|
|
</ADDRESS>
|
|
</CENTER>
|
|
|
|
</BODY>
|
|
</HTML>
|