> > then, what's the point to use binary search?
> 
> It seemed more natural to use binary search when the list is sorted..
> I guess I can revert.

to me, it's more natural to use a simple method
where complex ones are not necessary.

> > because it can send only limited number of groups.
> 
> Yes, I know that, but is it an implementation detail that the order
> by which the groups appear indicates their importance?

it's a matter of definition of group list, not an implementation detail.

> also, AFAIK
> both cr_groups and NFS's groups use NGROUPS of 16 for now.
> 
> In other words: it doesn't matter. :)

see mount_nfs -g option.

> Btw -- how is NFSv4 in this area?

there's no differences if you use AUTH_UNIX.

YAMAMOTO Takashi