Xref: utzoo comp.unix.questions:10334 comp.unix.wizards:12856
Newsgroups: comp.unix.questions,comp.unix.wizards
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: what is the 'l' permission?
Message-ID: <1988Nov25.213310.11511@utzoo.uucp>
Organization: U of Toronto Zoology
References: <71@attibr.UUCP> <4594@ptsfa.PacBell.COM> <483@auspex.UUCP> <4945@b-tech.ann-arbor.mi.us> <951@vsi.COM>
Date: Fri, 25 Nov 88 21:33:10 GMT

In article <951@vsi.COM> friedl@vsi.COM (Stephen J. Friedl) writes:
>I'm speculating on this part, but I guess that setting the `l' mode
>is required because the vast majority of programs don't use locking,
>and the overhead required on each read/write call is probably too much.

Consider a program that mandatory-locks /etc/passwd and then sleeps forever.
Antisocial, no?  So mandatory locking is available only on files that are
explicitly marked as "okay to lock".
-- 
Sendmail is a bug,             |     Henry Spencer at U of Toronto Zoology
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