x:\perl\site\lib\My\Tee.pm

##</code><code>##

package My::Tee;
use Tie::Handle;

our @ISA = qw[ Tie::Handle ];

sub TIEHANDLE {
	die "Usage: tie *STDxxx, 'My::Tee', 'logfilepath'"
		unless @_ == 2;

	open my $std, '>', 'CON'
		or die "Couldn't reopen STDxxx : $!"
		and return;

	my( $flush, $old ) = ( $|, select( $std ) );
	$| = $flush; select( $old );

	open my $log, '>', $_[1]
		or die "Couldn't open $_[1] for output: $!"
		and return;

	bless { log => $log, stdout => $std }, $_[0];
}

sub PRINT {
	my $self = shift;
	print { $self->{ log } } @_;
	print { $self->{ stdout } } @_;
}

sub PRINTF {
	my $self = shift;
	printf { $self->{ log } } @_;
	printf { $self->{ stdout } } @_;
}

1;

##</code><code>##

tie *STDxxx, 'My::Tee', '\path\to\logfile';