use the $SIG{__WARN__}: 
$SIG{__WARN__} = sub { die $_[0] };
warn "This will be fatal\n";
print "You will never get to this line\n";

[download]
See perlvar for more info.

In reply to Re: How can I tell at run time that my script is writing to STDERR? by zigdon
in thread How can I tell at run time that my script is writing to STDERR? by Dave05

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