|Pathologically Eclectic Rubbish Lister|
Re^4: OT: Locking and syncing mechanisms available on *nix.by BrowserUk (Pope)
|on Mar 27, 2011 at 12:22 UTC||Need Help??|
Ah. Okay. I don't use, nor have any time for the O'Woe dodo that is .NET, so that's of no use to me.
What I'm really looking for (I think) is a *nix equivalent to Windows Event Objects. Basically, a non-polling, non-spinning mechanism to have one thread block until another thread signals.
In theory, pthread condition variables ought to be usable for this. In practice, using a condition variable also requires the use of a mutex, which I don't need or want. I'm not trying to mutually exclude anything. Nor do I see a convenient place to put a mutex that I don't need.
I've run across a few mentions of something called a "futex" which is compared to Window's Event objects, but looking that term up it is defined as a 'fast user mutex'. Again, I'm not trying to mutually exclude anything!
The situation I'm trying to deal with would seem to be a relatively common occurrence. This thread has detected a situation that means it cannot proceed until some other thread does something. It therefore need to block until that other thread signals that it has been done. So, it reset an event and waits for it to be signalled. The other thread signals that event each time it does whatever it is required to do to allow the first thread to move forward.
But I don't see how to do this with *nix?
Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.