Re: real POSIX.1b semaphores

Theodore Y. Ts'o (
Wed, 20 Nov 1996 17:11:19 -0500

From: Ulrich Drepper <>
Date: 20 Nov 1996 19:13:22 +0100

> Because of the security problems, I don't believe global unnamed
> semaphores are useful.

But they have to be available. You can place the semaphore
descriptor in a shared memory segment and make it available to
other processes.

POSIX.1 always says:

>>Either the implemenation shall support the XXX function as described
above or the XXX function shall fail.<<

This means we really have to implement it.

True, we have to implement it. But we don't have to spend a lot of time
getting it super fast, or particularily elegant. I'd concetrate on
those parts of the POSIX.1b spec that are likely to be actually used by
real applications.....

- Ted