By default, the C<flock> call will block until a lock is granted.
A request for a shared lock will be granted as soon as there is no
-exclusive locker. A request for a exclusive lock will be granted as
+exclusive locker. A request for an exclusive lock will be granted as
soon as there is no locker of any kind. Locks are on file descriptors,
not file names. You can't lock a file until you open it, and you can't
hold on to a lock once the file has been closed.