Another problem with the current version is that it only overrides the given functions in the current package, so all modules and embedded packages must also use it to get the functionality you might want.

#!/usr/bin/perl -w
use strict;
use Fatal qw/open close/;

package Foo;
#use Fatal qw/open close/;
sub bar {
    open(FILE,'dfdsadf');
    close FILE;
}

package main;
Foo::bar();
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It should at least be a lexically scoped pragma so the above would be fatal without reissuing the use statement. I'm not sure how it could be made to globally overide such functions in all used packages.