Here's one cross-platform way to simultaneously print to STDOUT and a filehandle.

# print messages to both console and logfile
sub PrintLogCon {
  print @_;
  print(LOG @_) or die "Error printing to $logfile: $!";
  }
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and you'd call it thusly:

use warnings;
use strict;
open(LOG, ">$logfile") or die "Error opening $logfile: $!";
...
...
...
do->stuff;
do->it(again) or PrintLogCon("Error: $!");
do->stuff(more);
...
...
...
close LOG or die "Error closing $logfile: $!";
__END__
[download]

Phat props to mad monk Petruchio for showing me this a while back.
    cheers,
    Don
    striving toward Perl Adept
    (it's pronounced "why-bick")

Update2: consistant-ized scalar for logfile
Update1: or use IO::Tee as shown by fine monk jsprat.