Hi,

In message "[ruby-talk:01208] File#flock"
    on 00/01/31, ts <decoux / moulon.inra.fr> writes:

| The documentation say :
|
|  LOCK_EX 
|
|     Exclusive lock. Only one process may hold an exclusive lock for a
|                     ^^^^^^^^^^^^^^^^
|     given file at a given time.
|
| This is "Only one thread", no ?

No, File#flock is based on system call flock(2), which does not aware
of Ruby's threads.  For thread synchronization, use Mutex.