Is over-writing $! a good idea?

The errno values that pfaut(++) mentions are there for a reason.

What is wrong with supplying your error message to die (or warn, or any of the Carp methods) in the normal way:

die "Custom error messages are good!" if $condition;
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You don't have to include $! in your die statements, if you don't want to.

Alternatively, you can install a __DIE__ handler to override the default behaviour of die:

#!/usr/bin/perl

use strict;
use warnings;

local $SIG{__DIE__} = sub { die scalar localtime(), " " , $_[0] };

die "Argh!";
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produces:

Sat Jan 25 00:40:36 2003 Argh! at ./custom_die.pl line 8.
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