I have done this in the past, and it seems to work fine: 
my $file = $ARGV[0] ? $ARGV[0] : die "USAGE:  prog.pl file_pathname\n";
open(FILE,"$file") or die "Unable to open file $file\n";

In reply to Re^2: Testing <> for undefined by BbTrumpet
in thread Testing <> for undefined by kayak9630

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