$ ( sleep 10 ) | perl 409100.pl 
timed out with 0 lines

$ ( echo one; sleep 10 ) | perl 409100.pl 
timed out with 1 lines

$ ( echo one; echo two; sleep 10 ) | perl 409100.pl 
timed out with 2 lines

$ ( echo one; echo two; echo three; sleep 10 ) | perl 409100.pl 
didn't timeout with 3 lines