Re: 2.0.29 sysctl.c if(grp == current->euid)

David A Rusling (
Tue, 11 Feb 1997 07:12:01 +0000

I'm not sure either, I'm confused by Linux's use of uids and gids, for
every process it keeps 4 variants of each (plus an array of group ids):

uid, suid, euid, fsuid
gid, sgid, egid, fsgid

So far as I can tell from reading the code, the fsuid and fsgid are
used when checking access to files and they are there because some executables
may change the uid and gid of the executing process (for the purposes of
privilege protection). euid and egid are the effective ids (based on
{uid, suid} and {gid, sgid}?). If someone could clarify this it would be

The patch though does not make sense to me either...


David A Rusling Principal Engineer
European Semiconductor Applications Digital Equipment Co Ltd.,
Engineering PO Box 121,
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