trace("Child", "Child FH: ", fileno($s1a), "/", fileno($s2a));

        open(STDIN, "<&=" . fileno($s1a)) || die "dup of stdin failed";
        open(STDOUT, ">&=" . fileno($s2a)) || die "dup of stdout failed";
        open(STDERR, ">&STDOUT") || die "dup of stderr failed";

	shutdown($s1a, 1);
	close($s1b);
	shutdown($s2a, 0);
	close($s2b);

	exec @_;
	die;

    } else {

	close($s1a);
	shutdown($s1b, 0);
	close($s2a);
	shutdown($s2b, 1);

	$self->{INPUT} = $s2b;
	$self->{OUTPUT} = $s1b;
    }

    1;
}

#
# Initialize a tty's termio setting: turn off echo.
#
sub init_tty
{
    my($self, $fd) = @_;

    unless ($termios->getattr(fileno($fd))) {
        $self->{JUNOS_Device}->report_error("getattr failed on pty");
	return;
    }
    my $lflags = $termios->getlflag;
    $lflags &= ~(&ECHO);
    $termios->setlflag($lflags);
    $termios->setattr(fileno($fd));
    1;
}

#
# Start a command in a sub-process under a pty
#
sub start_command
{
    my $self = shift;

    tracept("IO");

    my $pty = new IO::Pty;
    my $slave = $pty->slave;

    unless ($slave) {
        $self->{JUNOS_Device}->report_error("cannot create pty slave");
	return;
    }
	
    trace("IO", "Access: pty $pty $$pty ", $pty->ttyname);
    trace("IO", "Access: slv $slave $$slave ", $slave->ttyname);

    &init_tty($self, $slave) || return;

    my $pid = fork;
    if ($pid < 0) {
        $self->{JUNOS_Device}->report_error("fork failed");
	return;
    } elsif ($pid == 0) {
	trace("Child", "Child $pid/", $$, " cmd: ", join(" ", @_));
	trace("Child", "Child FH: ", fileno($pty), "/", fileno($slave));

	# Turn the pty/tty into our stdin/stdout/stderr
	close(STDIN);
	open(STDIN, "<&" . fileno($slave)) || die "dup of stdin failed";
	shutdown(STDIN, 1);
	close(STDOUT);
	open(STDOUT, ">&" . fileno($slave)) || die "dup of stdout failed";
	shutdown(STDOUT, 0);
	close(STDERR);
	open(STDERR, ">&STDOUT") || die "dup of stderr failed";

	#
	# We need to disassociate ourselves from the controlling tty.
	# It would be nice to make the pty/tty we just made into our
	# controlling tty, but this does not seem to be working....
	#
        setsid;

	# Close off the original pty/tty handles
	close($slave);
	close($pty);

	exec @_;
	die;