Just to clarify this line from thundergnat's post: 
open my $fh, shift or die "Cannot open file: $!\n";

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shift(), when used outside a subroutine shifts the first element off @ARGV. Another way of accessing the first element would be: 
open my $fh, $ARGV[0] or die "Cannot open file: $!\n";

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See also perldata, perlvar and shift

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^2: Using @ARGV by Joost
in thread Using @ARGV by Tech77

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