#!perl -sw
use strict;
use vars qw/$f $s $t $debug/; #! This allows us to reference global vars without violating strict.
=pod comment only!
 Note: $::var is (assuming we are in main) shorthand for saying $main::var which is the same as
       $var if we aren't using strict and we haven't defined my $var at the current scope.
 (I'm sure that I haven't captured the all the semantics in this comment,
  but the Perl lawyers will correct me :)

 if -debug not on the command line, it would set my $debug to undef, which would cause warnings later
 when we try to do 'print "something\n" if $debug;'. we could use defined, but that's hard work.
=cut

my $debug	= $::debug || 0;
my $file	= $::f || 'd:/temp/temp.dat'; 	#! Use a tempfile by default
my $size	= $::s || 4096; 				#! default size
my $time	= $::t || time; 				#! default to now.

print <<OUT;
$0 will run with settings
debug: $debug
 file: $file
 size: $size
 time: $time
OUT

__END__
C:\test>210020
C:\test\210020.pl will run with settings
debug: 0
 file: d:/temp/temp.dat
 size: 4096
 time: 1036283982

C:\test>210020 -debug -f="./temp.dat" -s=8192
C:\test\210020.pl will run with settings
debug: 1
 file: ./temp.dat
 size: 8192
 time: 1036283985

C:\test>