NAME
getopt, getopts - Process single-character switches with switch clus-
teringSYNOPSIS
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 allswitches that take an argument. For each switch found, sets $optx
(where x is the switch name) to the value of the argument if an argu-
ment is expected, or 1 otherwise. Switches which take an argumentdon't care whether there is a space between the switch and the argu-
ment. The getopts() function is similar, but you should pass to it the list of all switches to be recognized. If unspecified switches are found onthe command-line, the user will be warned that an unknown option was
given. Note that, if your code is running under the recommended "use strict 'vars'" pragma, you will need to declare these package variables with "our":our($optx, $opty);
For those of you who don't like additional global variables being cre-
ated, 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 theargument "-". The "-" will be removed from @ARGV.
""--hheellpp"" and "-version"
If "-" is not a recognized switch letter, getopts() supports arguments
"-help" and "-version". If "main::HELPMESSAGE()" and/or "main::VER-
SIONMESSAGE()" are defined, they are called; the arguments are theoutput 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 inthe script, "-help" will also show how to access the documentation.
Note that due to excessive paranoia, if $Getopt::Std::STAN-
DARDHELPVERSION isn't true (the default is false), then the messages are printed on STDERR, and the processing continues after the messagesare printed. This being the opposite of the standard-conforming behav-
iour, it is strongly recommended to set $Getopt::Std::STAN-
DARDHELPVERSION to true. One can change the output file handle of the messages by setting$Getopt::Std::OUTPUTHELPVERSION. One can print the messages of
"-help" (without the "Usage:" line) and "-version" by calling func-
tions helpmess() and versionmess() with the switches string as an argument.perl v5.8.8 2001-09-21 Getopt::Std(3pm)