Re: Exhausting Locked SEM_UNDO Semaphores on MacOS

If you're confident that POSIX semaphores work well on MacOS, then go ahead and submit a patch to change the default selection for MacOS. Thanks.

Here are a couple of small possible patches for consideration (based on mdb.master3 branch): This is a trivial fix for several compilation errors (on Windows) due to unknown size of void on the mdb.master3 branch: https://github.com/kriszyp/lmdb/commit/12f1bdf9be5052728694eb5fa222688f50f84...

And then this patch makes POSIX semaphores the default on MacOS unless robust semaphores are specified (in which case it will go back to SysV semaphores): https://github.com/kriszyp/lmdb/commit/0971512f6a4aa5b05f99e481a6687d4802f70...

Thanks, Kris