package Filter::Handle;
use strict;
use Carp;

sub PRINT {
  my $self = shift;
  my $fh = $self->{fh};
  print $fh $self->{disp}->(@_);
}

sub PRINTF {
  my $self = shift;
  @_ = ($self, sprintf(shift, @_));
  goto &PRINT;
}

sub TIEHANDLE {
  my $class = shift;
  my $fh = shift or croak("Need a filehandle to tie to.");
  my $disp = shift ||
    sub {
      my ($file, $line) = (caller(1))[1,2];
      sprintf("%s:%d - %s\n", $file, $line, "@_");
    };
  return bless ({fh => $fh, disp => $disp}, $class);
}

# An OO interface for free! :-)
*new = *TIEHANDLE;
*print = *PRINT;
*printf = *PRINTF;

1;

##</code><code>##

my $out = new Filter::Handle(\*STDOUT);
$out->print("Hello world\n");
$out->printf("%s %s\n", "Hello", "world");

##</code><code>##

tie (*OUT, 'Filter::Handle', \*STDOUT);
select(OUT);
print "Hello world\n";
printf ("%s %s\n", "Hello", "world");