Re: Locking a script

Eeehm what I would do is to set up a temporary file with
a lock just before you enter your critical zone,
(first check if it's not there already ofcourse ;)) just unlock/unlink the file when you're done

Anyways, that's what I would do...

Comment on Re: Locking a script

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RE (tilly) 2 Locking a script by tilly (Archbishop) on Oct 18, 2000 at 14:40 UTC
You would have a serious race condition. Invocation 1 comes along, opens the file, and flocks it. Invocation 2 comes along, opens the file, and blocks on the flock. Invocation 1 leaves and unlinks the file, dropping the lock it had. Invocation 2 gets its lock on a temporary that only will exist until Invocation 2 is done. Invocation 3 comes along, sees no file, creates, flocks, and now Invocations 2 and 3 are running in parallel... (This is all with Unix filesystem semantics of course.)	[reply]
RE: RE (tilly) 2 Locking a script by ChOas (Curate) on Oct 18, 2000 at 15:24 UTC
Okay, okay.... Wasn't thinking heavy duty progamming for a sec. ;))) Dining Philosophers 'n stuff... How about a semaphore ? perldoc perlipc might give some clues...	[reply]
RE (tilly) 4 Locking a script by tilly (Archbishop) on Oct 18, 2000 at 15:27 UTC
That would work, in fact try IPC::Semaphore.	[reply]