use strict;
use warnings;
use subs qw(die);

# install my new die code
sub die { One (); Two (); print "Die.\n"; CORE::die @_; }

my $filename = "this file does not exist";

open (FH, $filename) or die "$filename: $!";
# do something
close (FH);

sub One { print "One . ";}
sub Two { print "Two . ";}