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NAME
       perl - Practical Extraction and Report Language

SYNOPSIS
       perl [ -sTuU ] [ -hv ] [ -V[:configvar] ]
           [ -cw ] [ -d[:debugger] ] [ -D[number/list] ]
           [ -pna ] [ -Fpattern ] [ -l[octal] ] [ -0[octal] ]
           [ -Idir ] [ -m[-]module ] [ -M[-]'module...' ]
           [ -P ] [ -S ] [ -x[dir] ]
           [ -i[extension] ]
       [ -e 'command' ] [ -- ] [ programfile ] [ argument ]...

       For ease of access, the Perl manual has been split up into
       several sections:

           perl                Perl overview (this section)
           perlfaq             Perl frequently asked questions
           perltoc             Perl documentation table of contents
           perlbook            Perl book information

           perlsyn             Perl syntax
           perldata            Perl data structures
           perlop              Perl operators and precedence
           perlsub             Perl subroutines
           perlfunc            Perl builtin functions
           perlreftut          Perl references short introduction
           perldsc             Perl data structures intro
           perlrequick         Perl regular expressions quick start
           perlpod             Perl plain old documentation
           perlstyle           Perl style guide
           perltrap            Perl traps for the unwary

           perlrun             Perl execution and options
           perldiag            Perl diagnostic messages
           perllexwarn         Perl warnings and their control
           perldebtut          Perl debugging tutorial
           perldebug           Perl debugging

           perlvar             Perl predefined variables
           perllol             Perl data structures: arrays of arrays
           perlopentut         Perl open() tutorial
           perlretut           Perl regular expressions tutorial

           perlre              Perl regular expressions, the rest of the story
           perlref             Perl references, the rest of the story

           perlform            Perl formats

           perlboot            Perl OO tutorial for beginners
           perltoot            Perl OO tutorial, part 1
           perltootc           Perl OO tutorial, part 2
           perlobj             Perl objects
           perlbot             Perl OO tricks and examples
           perltie             Perl objects hidden behind simple variables



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           perlipc             Perl interprocess communication
           perlfork            Perl fork() information
           perlnumber          Perl number semantics
           perlthrtut          Perl threads tutorial

           perlport            Perl portability guide
           perllocale          Perl locale support
           perlunicode         Perl unicode support
           perlebcdic          Considerations for running Perl on EBCDIC platforms

           perlsec             Perl security

           perlmod             Perl modules: how they work
           perlmodlib          Perl modules: how to write and use
           perlmodinstall      Perl modules: how to install from CPAN
           perlnewmod          Perl modules: preparing a new module for distribution

           perlfaq1            General Questions About Perl
           perlfaq2            Obtaining and Learning about Perl
           perlfaq3            Programming Tools
           perlfaq4            Data Manipulation
           perlfaq5            Files and Formats
           perlfaq6            Regexes
           perlfaq7            Perl Language Issues
           perlfaq8            System Interaction
           perlfaq9            Networking

           perlcompile         Perl compiler suite intro

           perlembed           Perl ways to embed perl in your C or C++ application
           perldebguts         Perl debugging guts and tips
           perlxstut           Perl XS tutorial
           perlxs              Perl XS application programming interface
           perlclib            Internal replacements for standard C library functions
           perlguts            Perl internal functions for those doing extensions
           perlcall            Perl calling conventions from C
           perlutil            utilities packaged with the Perl distribution
           perlfilter          Perl source filters
           perldbmfilter       Perl DBM filters
           perlapi             Perl API listing (autogenerated)
           perlintern          Perl internal functions (autogenerated)
           perlapio            Perl internal IO abstraction interface
           perltodo            Perl things to do
           perlhack            Perl hackers guide

           perlhist            Perl history records
           perldelta           Perl changes since previous version
           perl5005delta       Perl changes in version 5.005
           perl5004delta       Perl changes in version 5.004








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           perlaix             Perl notes for AIX
           perlamiga           Perl notes for Amiga
           perlbs2000          Perl notes for POSIX-BC BS2000
           perlcygwin          Perl notes for Cygwin
           perldos             Perl notes for DOS
           perlepoc            Perl notes for EPOC
           perlhpux            Perl notes for HP-UX
           perlmachten         Perl notes for Power MachTen
           perlmacos           Perl notes for Mac OS (Classic)
           perlmpeix           Perl notes for MPE/iX
           perlos2             Perl notes for OS/2
           perlos390           Perl notes for OS/390
           perlsolaris         Perl notes for Solaris
           perlvmesa           Perl notes for VM/ESA
           perlvms             Perl notes for VMS
           perlvos             Perl notes for Stratus VOS
           perlwin32           Perl notes for Windows

       (If you're intending to read these straight through for
       the first time, the suggested order will tend to reduce
       the number of forward references.)

       By default, the manpages listed above are installed in the
       /usr/local/man/ directory.

       Extensive additional documentation for Perl modules is
       available.  The default configuration for perl will place
       this additional documentation in the
       /usr/local/lib/perl5/man directory (or else in the man
       subdirectory of the Perl library directory).  Some of this
       additional documentation is distributed standard with
       Perl, but you'll also find documentation for third-party
       modules there.

       You should be able to view Perl's documentation with your
       man(1) program by including the proper directories in the
       appropriate start-up files, or in the MANPATH environment
       variable.  To find out where the configuration has
       installed the manpages, type:

           perl -V:man.dir

       If the directories have a common stem, such as
       /usr/local/man/man1 and /usr/local/man/man3, you need only
       to add that stem (/usr/local/man) to your man(1) configu-
       ration files or your MANPATH environment variable.  If
       they do not share a stem, you'll have to add both stems.

       If that doesn't work for some reason, you can still use
       the supplied perldoc script to view module information.
       You might also look into getting a replacement man pro-
       gram.

       If something strange has gone wrong with your program and



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       you're not sure where you should look for help, try the -w
       switch first.  It will often point out exactly where the
       trouble is.

DESCRIPTION
       Perl is a language optimized for scanning arbitrary text
       files, extracting information from those text files, and
       printing reports based on that information.  It's also a
       good language for many system management tasks.  The lan-
       guage is intended to be practical (easy to use, efficient,
       complete) rather than beautiful (tiny, elegant, minimal).

       Perl combines (in the author's opinion, anyway) some of
       the best features of C, sed, awk, and sh, so people famil-
       iar with those languages should have little difficulty
       with it.  (Language historians will also note some ves-
       tiges of csh, Pascal, and even BASIC-PLUS.)  Expression
       syntax corresponds closely to C expression syntax.  Unlike
       most Unix utilities, Perl does not arbitrarily limit the
       size of your data--if you've got the memory, Perl can
       slurp in your whole file as a single string.  Recursion is
       of unlimited depth.  And the tables used by hashes (some-
       times called "associative arrays") grow as necessary to
       prevent degraded performance.  Perl can use sophisticated
       pattern matching techniques to scan large amounts of data
       quickly.  Although optimized for scanning text, Perl can
       also deal with binary data, and can make dbm files look
       like hashes.  Setuid Perl scripts are safer than C pro-
       grams through a dataflow tracing mechanism that prevents
       many stupid security holes.

       If you have a problem that would ordinarily use sed or awk
       or sh, but it exceeds their capabilities or must run a
       little faster, and you don't want to write the silly thing
       in C, then Perl may be for you.  There are also transla-
       tors to turn your sed and awk scripts into Perl scripts.

       But wait, there's more...

       Begun in 1993 (see the perlhist manpage), Perl version 5
       is nearly a complete rewrite that provides the following
       additional benefits:

       o   modularity and reusability using innumerable modules

           Described in the perlmod manpage, the perlmodlib man-
           page, and the perlmodinstall manpage.

       o   embeddable and extensible

           Described in the perlembed manpage, the perlxstut man-
           page, the perlxs manpage, the perlcall manpage, the
           perlguts manpage, and the xsubpp manpage.




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       o   roll-your-own magic variables (including multiple
           simultaneous DBM implementations)

           Described in the perltie manpage and the AnyDBM_File
           manpage.

       o   subroutines can now be overridden, autoloaded, and
           prototyped

           Described in the perlsub manpage.

       o   arbitrarily nested data structures and anonymous func-
           tions

           Described in the perlreftut manpage, the perlref man-
           page, the perldsc manpage, and the perllol manpage.

       o   object-oriented programming

           Described in the perlobj manpage, the perltoot man-
           page, and the perlbot manpage.

       o   compilability into C code or Perl bytecode

           Described in the B manpage and the B::Bytecode man-
           page.

       o   support for light-weight processes (threads)

           Described in the perlthrtut manpage and the Thread
           manpage.

       o   support for internationalization, localization, and
           Unicode

           Described in the perllocale manpage and the utf8 man-
           page.

       o   lexical scoping

           Described in the perlsub manpage.

       o   regular expression enhancements

           Described in the perlre manpage, with additional exam-
           ples in the perlop manpage.

       o   enhanced debugger and interactive Perl environment,
           with integrated editor support

           Described in the perldebug manpage.

       o   POSIX 1003.1 compliant library




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           Described in the POSIX manpage.

       Okay, that's definitely enough hype.

AVAILABILITY
       Perl is available for most operating systems, including
       virtually all Unix-like platforms.  See the Supported
       Platforms entry in the perlport manpage for a listing.

ENVIRONMENT
       See the perlrun manpage.

AUTHOR
       Larry Wall <larry@wall.org>, with the help of oodles of
       other folks.

       If your Perl success stories and testimonials may be of
       help to others who wish to advocate the use of Perl in
       their applications, or if you wish to simply express your
       gratitude to Larry and the Perl developers, please write
       to perl-thanks@perl.org .

FILES
        "@INC"                 locations of perl libraries


SEE ALSO
        a2p    awk to perl translator
        s2p    sed to perl translator

        http://www.perl.com/       the Perl Home Page
        http://www.perl.com/CPAN   the Comprehensive Perl Archive


DIAGNOSTICS
       The "use warnings" pragma (and the -w switch) produces
       some lovely diagnostics.

       See the perldiag manpage for explanations of all Perl's
       diagnostics.  The "use diagnostics" pragma automatically
       turns Perl's normally terse warnings and errors into these
       longer forms.

       Compilation errors will tell you the line number of the
       error, with an indication of the next token or token type
       that was to be examined.  (In a script passed to Perl via
       -e switches, each -e is counted as one line.)

       Setuid scripts have additional constraints that can pro-
       duce error messages such as "Insecure dependency".  See
       the perlsec manpage.

       Did we mention that you should definitely consider using
       the -w switch?



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BUGS
       The -w switch is not mandatory.

       Perl is at the mercy of your machine's definitions of var-
       ious operations such as type casting, atof(), and float-
       ing-point output with sprintf().

       If your stdio requires a seek or eof between reads and
       writes on a particular stream, so does Perl.  (This
       doesn't apply to sysread() and syswrite().)

       While none of the built-in data types have any arbitrary
       size limits (apart from memory size), there are still a
       few arbitrary limits:  a given variable name may not be
       longer than 251 characters.  Line numbers displayed by
       diagnostics are internally stored as short integers, so
       they are limited to a maximum of 65535 (higher numbers
       usually being affected by wraparound).

       You may mail your bug reports (be sure to include full
       configuration information as output by the myconfig pro-
       gram in the perl source tree, or by "perl -V") to perl-
       bug@perl.org .  If you've succeeded in compiling perl, the
       perlbug script in the utils/ subdirectory can be used to
       help mail in a bug report.

       Perl actually stands for Pathologically Eclectic Rubbish
       Lister, but don't tell anyone I said that.

NOTES
       The Perl motto is "There's more than one way to do it."
       Divining how many more is left as an exercise to the
       reader.

       The three principal virtues of a programmer are Laziness,
       Impatience, and Hubris.  See the Camel Book for why.





















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