$| = 1;
 undef $/; # or not if slurping to array.
 
 my $file;
my @file;
 my $START_TIME = time;

 my $filename = 'C:\Documents and Settings\ron\My Documents\FGwing\new_rptgen\DATA\run001\ENG_mod.262-08_41_43'; # substitute your own big file
 
 open (FILE, "$filename") or die "can't open $filename";
 
 $file = <FILE>; # or @file= <FILE>;
 
 sub END{
 	my $END_TIME = time;
 	my $RUN_TIME = $END_TIME - $START_TIME;
 	print STDOUT "\n\n Phew, that took $RUN_TIME seconds.\n\n";
 }