This one makes some sense when you think about it in terms of say NFS et al...

uid=-1, gid=-1 => nobody/unknown on NFS/PCNFS
uid=-2, gid=-2 => bad root access over NFS/PCNFS - see exports(5)

Thus, the max valid value for uid/gid is (signed int) -3, or 2^31-2 (-1 is 2^32,
-2 is 2^31-1) assuming that uid and gid are 32 bit ints (try teaching that to
e.g. a SunOS 4.x machine that just mounted you - it uses 16 bit ints but thats
another matter entirely :)

P.

Geoff Wing wrote:

> 4) Another interesting thing: <sys/syslimits.h>
> #define GID_MAX            2147483647U  /* max value for a gid_t (2^31-2) */
> #define UID_MAX            2147483647U  /* max value for a uid_t (2^31-2) */
>                                                                       ^^
>                                                                       yeah?

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| Paul Wain                         || Tel: +1 650 631 GOAT (4628)     |
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