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Posting-Version: version B 2.10.1 6/24/83; site ki4pv.UUCP
Path: utzoo!watmath!clyde!burl!ulysses!allegra!ki4pv!tanner
From: tanner@ki4pv.UUCP (Tanner Andrews)
Newsgroups: net.bugs.4bsd
Subject: Re: EXCL without CREAT
Message-ID: <7022@ki4pv.UUCP>
Date: Wed, 18-Dec-85 10:09:11 EST
Article-I.D.: ki4pv.7022
Posted: Wed Dec 18 10:09:11 1985
Date-Received: Sat, 21-Dec-85 01:26:46 EST
References: <5507@allegra.UUCP>, <6220@utzoo.UUCP>
Organization: CompuData South, DeLand
Lines: 12

] utzoo!henry points out problem of fool opening/locking /etc/passwd
] and claims that adding open("arg", O_READ|EXCL) re-invents flock()

Doesn't re-invent flock() -- open()/flock() is not an atomic action.

Security is easily solved by refusing to allow locking a file unless
the file has been successfully opened for WRITE -- there's no real
excuse for a read-only prog to need to lock a file if the write-file
prog successfully locks the damned thing anyway.
-- 
<std dsclm, copies upon request>	   Tanner Andrews, KI4PV
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