I'm not sure that I understand why you can't bit-wise xor two strings: 
$foo = "baz"; 
$bar = "foo";

print unpack("B*", $foo); 
print unpack("B*", $bar); 
print unpack("B*", ($bar ^ $foo));
__END__
011000100110000101111010
011001100110111101101111
000001000000111000010101

[download]
Seems to do the right thing to me...

thor

In reply to Re: Re: Re: Mod-2 add 2 binary files by thor
in thread Mod-2 add 2 binary files by tperdue

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