If you are seeing it twice you are probably printing the error message in your handler. If you don't wrap your die in an eval you will see the message twice...

erickn@isfe:/home/erickn> cat y 
$SIG{__DIE__} = sub { print $_[0] };

die "hi";



erickn@isfe:/home/erickn> perl y
hi at y line 4.
hi at y line 4.
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Wrapping in an eval will stop it...

erickn@isfe:/home/erickn> cat x

$SIG{__DIE__} = sub { print $_[0] };

eval {
   die "hi";
};



erickn@isfe:/home/erickn> perl x
hi at x line 5.
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