I think that you were after something like this: 
#!/usr/bin/perl

use strict;
use warnings;

BEGIN {
    *CORE::GLOBAL::open = sub (*;$@) {
        if(defined($_[0])) {
            use Symbol qw();
            my $handle = Symbol::qualify($_[0], (caller)[0]);
            no strict 'refs';
            if(@_ == 1) {
                return CORE::open($handle);
            }
            elsif(@_ == 2) {
                return CORE::open($handle, $_[1]);
            }
            else {
                return CORE::open($handle, $_[1], @_[2..$#_]);
            }
        }                
    };               
}

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As I understand it, to override globally, you need to use CORE::GLOBAL in a BEGIN block because it has to be done at compile time.

In reply to Re: Override the open builtin globally by Khen1950fx
in thread Override the open builtin globally by ninuzzo

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