Getopt::Std + Pod::Usage

#!/usr/bin/perl -w

use strict;

use Getopt::Std;
use Pod::Usage;

my(%opt);

getopts('csf:?', \%opt)
  or pod2usage(-exitstatus => 1, -verbose => 0);

pod2usage(-exitstatus => 0, -verbose => 2) if($opt{'?'});

sanitise_files(\%opt, @ARGV);

exit 0;


__END__

=head1 NAME

sanitise - clean up files by removing microbes

=head1 SYNOPSIS

  sanitise [options] <files>

  Options:

   -c     clean files
   -s     shine files
   -f x   select fragrance (x = pine, meadow or toast)
   -?     detailed help message

=head1 DESCRIPTION

This imaginary script strikes with the power of liquid
lightning to sanitise your files by removing unwanted
microbes.  Use strictly as directed.  Conditions apply.

=head1 OPTIONS

=over 4

=item B<-c>

Enable the cleaning mode.

=item B<-s>

Enable the shining mode.  (Note these options can be
combined for the ultimate clean and shine).

=item B<-?>

Display this documentation.

=back

=head1 COPYRIGHT

Copyright 2005 Grant McLean E<lt>grantm@cpan.orgE<gt>

This library is free software; you can redistribute it
and/or modify it under the same terms as Perl itself.

=cut

• Output:

$ ./02_getopt_usage.pl -p
Unknown option: p
Usage:
      sanitise [options] <files>

      Options:

       -c     clean files
       -s     shine files
       -f x   select fragrance (x = pine, meadow or toast)
       -?     detailed help message