Hello wise monks. I'd just like to know if file locking in perl is fail safe. If I have something like this in my code: 
sub get_lock
{
  open(SEM, ">$semaphore_file") || die "Cannot create semaphore: $!";
  flock(SEM, LOCK_EX) || die "Lock failed: $!";
}
sub release_lock
{
  close(SEM);
}
$semaphore_file="semfile";
get_lock();
#Do something here
release_lock;

[download]
Would any other instance of the same program be able to get passed the get_lock(); line without obtaining a lock first? Shouldn't the get_lock(); line make all instances of the same program "wait their turn" to get a lock before proceeding so that only one instance of the program gets to "Do something here" at a time? Thanks in advance.

In reply to Lock Effectivity by Gorby

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