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Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!att!ulysses!andante!alice!wilber
From: wilber@alice.UUCP (Bob Wilber)
Newsgroups: comp.unix.questions,comp.unix.wizards
Subject: Re: at files and permissions
Message-ID: <9588@alice.UUCP>
Date: 9 Jul 89 21:29:06 GMT
Organization: AT&T Bell Laboratories, Murray Hill NJ
Lines: 13

Brandon S. Allbery writes:
>at needs root permissions so it can setuid() itself to the owner of the at
>job file, so it can execute the job as the user who submitted it.

No.  "at" doesn't execute the job file, "atrun" does.  (Or, on some systems,
cron itself.)  "at" only needs the ability to create a file in the at spool
directory.  As I stated in my previous post, this shouldn't require root
capabilities, but on System V, a bug in the setuid(2) command forces "at"
to be run setuid to root.

Bob Wilber