Re: glibc-2.0.94: <sys/sem.h> doesn't include union semun

[Zack Weinberg <zack@rabi.phys.columbia.edu>]

On 19 Jun 1998 09:23:05 +0200, Andreas Jaeger wrote:
>>>>>> Horst von Brand writes:
>
> > This is what semctl(2) seems to specify, anyway. This makes util-linux-2.8b
> > fail its build. Andries.Brouwer@cwi.nl told me <sys/sem_buf.h> (which
> > contains the definition) is not mentioned by either SYSV or X/OPEN.
>
><sys/sem_buf.h> is only in glibc 2.0 - glibc 2.1 doesn't contain
><sys/sem_buf.h> but <bits/sem.h> where the lack of union semun is
>documented.

This has always bugged me a little.  It seems silly to define an
interface but not provide the types needed to use it.  I assume
there's some standards requirement?  Would it be out of the question
for us to provide the union under _GNU_SOURCE, or perhaps more
usefully to set up something akin to the transparent union magic used
for struct sockaddr?  (since it seems the purpose of this union is to
allow passing several different things as the fourth arg to semctl)

zw