#! perl -slw
use strict;
use Term::ReadKey;

$| = 1;

sub ReadLine {
	my $timeout =  shift;
	my $start = time;
	ReadMode 1;
	my $buf;
	while( time < $start + $timeout ) {
		if( my $c = ReadKey 0.5 ) {
			printf $c;
			$buf .= $c;
			
			ReadMode( 0 ), return $buf if ord( $c ) == 13;
		}
	}
	ReadMode 0;
	return undef;
}
	

for my $n ( 1 .. 10 ) {
	if( my $buf = ReadLine( 10 ) ) {
		print "$n Got $buf";
	}
	else {
		print "$n timed out";
	}
	
}
__END__
[16:35:02.57] P:\test>alarmed.pl
Subroutine ReadLine redefined at P:\test\alarmed.pl line 7.
1 Got fred
2 Got bill
3 Got John
4 timed out
5 timed out
6 timed out
7 Got blech
8 Got one
9 Got two three
10 Got four