See the current Perl documentation for Getopt::Std.
Here is our local, out-dated (pre-5.6) version:
getopt - Process single-character switches with switch clustering
getopts - Process single-character switches with switch clustering
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
getopt() functions processes
single-character switches with switch clustering. Pass one argument which
is a string containing all switches that take an argument. For each switch
$opt_x (where x is the switch name) to the value
of the argument, or 1 if no argument. Switches which take an argument don't
care whether there is a space between the switch and the argument.
Note that, if your code is running under the recommended
'vars' pragma, it may be helpful to declare these package variables via
use vars perhaps something like this:
use vars qw/ $opt_foo $opt_bar /;
For those of you who don't like additional variables being created,
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.