When are infinite loops are useful in PHP?

Question

While reading through the great online PHP tutorials of Paul Hudson he said

Perhaps surprisingly, infinite loops can sometimes be h

Answer 1

For user input...

while True:
    input = get_input_from_user("Do you want to continue? ")
    if input not in ("yes", "y", "no", "n"):
        print "invalid input!"
    else: 
        break