use strict;
use warnings;
use Getopt::Long;
{
    my $blah;
    my $result = GetOptions('blah=i'    =>  \$blah);

    &usage unless $blah;
    print "result = $result\n";
    print "blah = $blah\n";
}
sub usage {
    print "$0: -blah=value\n"
}