Re: setgroups

[Rob Browning]

address@hidden (Paul Jarc) writes:

> unsigned long lgid = SCM_INUM (foo);
> GETGROUPS_T gid = lgid;
> if (gid < 0 || lgid != (unsigned long) gid) overflow;
>
> - Is SCM_INUM guaranteed to fit in unsigned long?  If not, what type
>   can we use instead?

I believe scm_t_bits (there's also scm_t_signed_bits) may be what you
want.

> - If GETGROUPS_T is signed and "gid = lgid" overflows, the C standard
>   says it's undefined behavior.  Are we worried about that, or are we
>   confident that it'll just wrap on platforms we care about?

I wondered about signed vs unsigned gid_t too...

-- 
Rob Browning
rlb @defaultvalue.org, @linuxdevel.com, and @debian.org
Previously @cs.utexas.edu
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