Getopt::Std(3pm) Perl Programmers Reference Guide Getopt::Std(3pm)

NAME
       getopt, getopts - Process single-character switches with switch
       clustering

SYNOPSIS
           use Getopt::Std;

           getopt('oDI');    # -o, -D & -I take arg.  Sets $opt* as a side effect.
           getopt('oDI', \%opts);    # -o, -D & -I take arg.  Values in %opts
           getopts('oif:');  # -o & -i are boolean flags, -f takes an argument
                             # Sets $opt* as a side effect.
           getopts('oif:', \%opts);  # options as above. Values in %opts

DESCRIPTION
       The getopt() function processes single-character switches with switch
       clustering.  Pass one argument which is a string containing all
       switches that take an argument.  For each switch found, sets $optx
       (where x is the switch name) to the value of the argument if an
       argument is expected, or 1 otherwise.  Switches which take an argument
       don't care whether there is a space between the switch and the
       argument.

       The getopts() function is similar, but you should pass to it the list
       of all switches to be recognized.  If unspecified switches are found on
       the command-line, the user will be warned that an unknown option was
       given.  The getopts() function returns true unless an invalid option
       was found.

       Note that, if your code is running under the recommended "use strict
       'vars'" pragma, you will need to declare these package variables with
       "our":

           our($optx, $opty);

       For those of you who don't like additional global variables being
       created, getopt() and getopts() will also accept a hash reference as an
       optional second argument.  Hash keys will be x (where x is the switch
       name) with key values the value of the argument or 1 if no argument is
       specified.

       To allow programs to process arguments that look like switches, but
       aren't, both functions will stop processing switches when they see the
       argument "".  The "" will be removed from @ARGV.

"help" and "version"
       If "-" is not a recognized switch letter, getopts() supports arguments
       "help" and "version".  If "main::HELPMESSAGE()" and/or
       "main::VERSIONMESSAGE()" are defined, they are called; the arguments
       are the output file handle, the name of option-processing package, its
       version, and the switches string.  If the subroutines are not defined,
       an attempt is made to generate intelligent messages; for best results,
       define $main::VERSION.

       If embedded documentation (in pod format, see perlpod) is detected in
       the script, "help" will also show how to access the documentation.

       Note that due to excessive paranoia, if
       $Getopt::Std::STANDARDHELPVERSION isn't true (the default is false),
       then the messages are printed on STDERR, and the processing continues
       after the messages are printed.  This being the opposite of the
       standard-conforming behaviour, it is strongly recommended to set
       $Getopt::Std::STANDARDHELPVERSION to true.

       One can change the output file handle of the messages by setting
       $Getopt::Std::OUTPUTHELPVERSION.  One can print the messages of
       "help" (without the "Usage:" line) and "version" by calling
       functions helpmess() and versionmess() with the switches string as an
       argument.



perl v5.16.3                      2013-03-04                  Getopt::Std(3pm)