my $state = 1;
ioctl( $handle, 0x8004667e, \$state );
my $end = time() + $timeout;
while( time() < $end and $buffer !~ m[\n] ) {
    my $read = sysread( $handle, $buffer, 100, length( $buffer ) );
    sleep 1;
}
$state = 0;
ioctl( $handle, 0x8004667e, \$state );