#!/usr/bin/perl -w
                                                                                
# Strict
use strict;
use warnings;
use File::Basename;
                                                                                
# Main program
print "Check file before unlink\n"; sleep 1;   system("ls $0; df -k $0");
print "Unlinking the file $0\n";    sleep 1;   unlink $0;
print "Check file after unlink\n";  sleep 1;   system("ls $0; df -k " . dirname($0));
                                                                                
print "File should be now be gone from disk (but still in memory)\n";
print "Try ^Z and check it with 'ls $0' ... (come back with 'fg')\n";
sleep 10;

1 while <DATA>; # ensure we use the *DATA filehandle in case perl optimises it away

print "I'm still here, but the original file is long gone.\n";

__END__
foo