$sel = IO::Select->new();
$sel->add(\*STDIN);

while(1)
{
    print "waiting to read:\n";
    my @handles = $sel->can_read();
    print "can read\n";

    foreach $h (@handles)
    {
        if($h == \*STDIN)
        {
            my $line = <STDIN>;
            my $finish = do_something_with_line($line);
        }
    }
    if($finish) {last;}
}