I currently use a logging object I wrote to manage messages. When something's going wrong, my rule of the thumb is to write the message to the log object, then to return undef. something like :

use strict;
use warnings;

package bozo;

use Message;

sub failing {
    my $log = Message->new ;
    $log->set_error("this always fails");
    return
}

package main;

use Message;

my $log = Message->new ;

# I sometimes do this
eval { `touch /toto` };
if ($@) { $log->set_error("it failed! : $@") ;

# or this
if  ( not 0 ) {
    $log->set_error("it failed too!")
}

# now calling the failing sub up there:
if ( not bozo::failing() ) {
    print $log->get_message();
}
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Whatever I do with the error string, the Message object also spits out errors and messages to the log, this way (PID, date and time, the the message):

[25435] 2006-02-21 14:27:20 : ERROR : DBD::Pg::st execute failed: exec
+ute on disconnected handle at ../lib/Archiver/Job.pm line 96.
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