Subject: Re: poll(2) oddity
To: <>
From: David Laight <>
List: tech-userlevel
Date: 07/09/2002 15:00:23
> Erm, I think that's the case, yes.  Indeed, I think it's technically wrong
> for us to define OPEN_MAX in <limits.h> unless {OPEN_MAX} is actually
> invariant at run time.

The SuS limits.h page does seem to differenciate between 'Runtime Invariant
Values (Possibly Indeterminate)' and 'Runtime Increasable Values'.  The
former should not be in limits.h if they can be increased whereas the latter
should be in limits.h.

However why some items are in one list and not in the other is
not at all obvious.  NGROUPS_MAX is 'runtime increasable' (so has
to be in limits.h) all the other 'kernel' constants should be absent
from limits.h unless the values are fixed for the implementation!

I wonder what the rational for that was?


David Laight: