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Re: [Fwd: [sem_* functions in cygwin]]

[Oops, I've sent this to Gerrit by PM instead of to the list. 
 Just resending it now for the records]

On Dec 12 14:54, Gerrit P. Haase wrote:
> Corinna Vinschen wrote:
> >>----- Forwarded message from "Gerrit P. Haase" -----
> >>nearly all sem_* functions are available, but sem_unlock is missing,
> >>was there a problem implementing sem_unlock() or was it just missed
> >>by accident?
> >>Gerrit
> >>----- End forwarded message -----
> >
> >I guess you're asking about sem_unlink().  It's not implemented so far
> >since named POSIX semaphores are implemented using named Windows 
> >semaphores. The SUSv3 description contains a pretty unfortunate 
> >implementation detail:
> >
> >  Calls to sem_open() to recreate or reconnect to the semaphore refer
> >  to a new semaphore after sem_unlink() is called.
> >
> >There's no way I know of, which allows to implement this using named
> >Windows semaphores.  At least not without adding a lot of annoying
> >bookkeeping overhead, possibly involving cygserver.
> I got an undefined reference to sem_unlock().

There's no such function defined in SUSv3.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader
Red Hat, Inc.

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