use strict;
use warnings;
use Getopt::Long;
use vars qw($opt_u $opt_h $opt_a $opt_l);

&GetOptions('l=s','u','h','a') || exit 1;

print "Option found: u\n" if ($opt_u);
print "Option found: h\n" if ($opt_h);
print "Option found: a\n" if ($opt_a);
if ($opt_l) {
    print "Option found: l\n";
    print "  with value: $opt_l\n";
} else {
    print "You must specify -l\n";
    exit 1;
}