You can do things like: 
package TwoWayHandle;

sub TIEHANDLE {
  my ($class, $in, $out) = @_;
  bless [ \$in, \$out ], $class;
}

sub PRINT {
  my $self = shift;
  local *FH = ${ $self->[1] };
  print FH @_;
}

sub READLINE {
  my $self = shift;
  local *FH = ${ $self->[0] };
  <FH>;
}

1;

[download]
And then use it as: 
use TwoWayHandle;
tie *ACDC, TwoWayHandle => (
  *STDIN,
  *STDOUT,
) or die "can't tie *ACDC: $!";

print ACDC "What's your name? ";
$name = <ACDC>;
chomp $name;
print ACDC "Hello, $name.\n";

[download]
Not sure why, but I can't call chomp() at the same time I read from the filehandle.

japhy -- Perl and Regex Hacker

In reply to Re: Munging STDIN and STDOUT into one handle by japhy
in thread Munging STDIN and STDOUT into one handle by Rhandom

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