use Getopt::Std;

getopt('oDI');    # -o, -D & -I take arg.  Sets opt_* as a side effect.
getopts('oif:');  # -o & -i are boolean flags, -f takes an argument.
                  # Sets opt_* as a side effect.
*****
getopt('dV');
*****
myscr -bfd January -V 10.4
*****
$opt_b = 1;
$opt_f = 1;
$opt_d = "January";
$opt_V = 10.4;
*****
myscr -bfdJanuary -V10.4
*****
getopts('a:bc:');
*****
myscr -abc    # WRONG unless bc is really the argument that belongs with -a
myscr -a -bc  # WRONG, with same qualification
myscr -a foo -bc bar    # $opt_a = "foo"; $opt_b = 1; $opt_c = "bar"
myscr -bafoo -cbar      # same as previous
*****
use strict;
use vars qw($opt_o $opt_i $opt_D);
use Getopt::Std;