Re: semaphores

[Ross Johnson <rpj@ise.canberra.edu.au>]

On Tue, 20 Apr 1999, Michael Ambrus wrote:

> Hi,
> I've tried the new semaphores and they seem to work fine except that errno
> is not properly set as Ross said.

Are you using the 1999-04-07 snapshot? Anything before that should
be upgraded. Can you provide me with some code that illustrates the
problem? The simple test I wrote (tests/errno1.c in the source tree)
checks that two threads can set and retrieve values of errno
independently. The test succeeds for MSVC (tested on WinNT) and
Mingw32 (tested on Win98).

> I'm confused about the "pshared" attribute
> though. Should it not be != 0 if the semaphore is to be shared between
> processes/treads ?

pshared should be non-zero for shared semaphores, however,
pthreads-win32 doesn't yet support any process shared objects. So
sem_init should return EPERM if you set pshared != 0.

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