Xref: utzoo comp.unix.programmer:1237 alt.sources.d:1571
Path: utzoo!utgpu!cs.utexas.edu!chinacat!sequoia!rpp386!jfh
From: jfh@rpp386.cactus.org (John F Haugh II)
Newsgroups: comp.unix.programmer,alt.sources.d
Subject: Re: -x implementations
Message-ID: <19091@rpp386.cactus.org>
Date: 7 Mar 91 13:14:29 GMT
References: <1943:Jan2619:34:3591@kramden.acf.nyu.edu> <2856@charon.cwi.nl> <8869@star.cs.vu.nl> <1991Jan29.153242.12335@convex.com> <8896@star.cs.vu.nl> <19017@rpp386.cactus.org> <6124@segue.segue.com> <668288533.3106@mindcraft.com>
Reply-To: jfh@rpp386.cactus.org (John F Haugh II)
Organization: Lone Star Cafe and BBS Service
Lines: 17
X-Clever-Slogan: Recycle or Die.

In article <668288533.3106@mindcraft.com> karish@mindcraft.com (Chuck Karish) writes:
>It would be helpful if there were a second interface that could be used
>to check file access based on the effective UID.  Adding a flag to
>access() at this point would not be an acceptable solution; it would
>break too much existing code.

IBM did exactly this with AIX v3.  They have a system call, accessx(),
which takes a flag as an additional parameter to determine who should
be tested for.  You can test for yourself as real id, yourself as
effective id, some notion of "anyone", and some notion of "everyone".
It does all the magic of checking for extended access control lists
and so on.
-- 
John F. Haugh II        | Distribution to  | UUCP: ...!cs.utexas.edu!rpp386!jfh
Ma Bell: (512) 832-8832 | GEnie PROHIBITED :-) |  Domain: jfh@rpp386.cactus.org
"I've never written a device driver, but I have written a device driver manual"
                -- Robert Hartman, IDE Corp.