#!/usr/local/apps/perl/bin/perl
#############################################################################
#                                                                           #
#  WHO:    John L. Moreland                                                 #
#                                                                           #
#  WHAT:   cmdline                                                          #
#                                                                           #
#  WHY:    Demonstrates one command line parsing technique.                 #
#                                                                           #
#  WHERE:  Opus Software                                                    #
#                                                                           #
#  WHEN:   Tue Sep 29 21:21:13 PDT 1998                                     #
#                                                                           #
#  HOW:    PERL                                                             #
#                                                                           #
#############################################################################

while ( @ARGV )
{
	$arg = shift( @ARGV );

	if ( $arg =~ /^-[acx]$/ ) {
		# Handle single-character options
		$opt{$arg} = 1;
		# Could do compound option handling here...
	} elsif ( $arg eq "-help" ) {
		# Handle multi-character options
		$opt{$arg} = 1;
	} elsif ( $arg eq "-f" ) {
		# Handle options with arguments
		$opt{$arg} = shift( @ARGV );
		if ( ($opt{$arg} eq "") || ($opt{$arg} =~ /^-/) )
		{
			print STDERR "The $arg option requires an argument\n";
			exit;
		}
	} elsif ( -f $arg ) {
		# Handle input or output file arguments
		@files = ( @files, $arg );
	} else {
		# Handle unknown arguments
		print "Invalid argument: $arg\n";
		print "Usage: $0 [-a] [-c] [-x] [-help] [-f optarg] [files]\n";
		exit;
	}
}

print "Options:\n"  if ( %opt );
foreach $key ( keys %opt )
{
	print "   $key = $opt{$key}\n";
}
print "Files:\n"  if ( @files );
foreach $file ( @files )
{
	print "   $file\n";
}