Xref: utzoo comp.unix.questions:10414 comp.unix.wizards:13037
Path: utzoo!utgpu!watmath!clyde!att!osu-cis!tut.cis.ohio-state.edu!unmvax!ncar!tank!nic.MR.NET!hal!ncoast!allbery
From: allbery@ncoast.UUCP (Brandon S. Allbery)
Newsgroups: comp.unix.questions,comp.unix.wizards
Subject: Re: what is the 'l' permission?
Message-ID: <13195@ncoast.UUCP>
Date: 1 Dec 88 00:22:29 GMT
References: <71@attibr.UUCP> <4594@ptsfa.PacBell.COM> <483@auspex.UUCP> <4945@b-tech.ann-arbor.mi.us> <951@vsi.COM>
Reply-To: allbery@ncoast.UUCP (Brandon S. Allbery)
Followup-To: comp.unix.questions
Organization: Cleveland Public Access UN*X, Cleveland, Oh
Lines: 23
As quoted from <951@vsi.COM> by friedl@vsi.COM (Stephen J. Friedl):
+---------------
> (re: the "l" mode bit in SVR3.2 and mandatory/advisory file locking)
|
| 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.
| Setting the lock bit probably enables this checking.
+---------------
No, it's because advisory file locking is the SVR3 standard, but mandatory
file locking was in Xenix. So UNIX apps use standard file locking and
migrated Xenix apps should set the "l" bit in order to work correctly.
I dunno, the whole thing seems a bit klugey to me.
++Brandon
--
Brandon S. Allbery, comp.sources.misc moderator and one admin of ncoast PA UN*X
uunet!hal.cwru.edu!ncoast!allbery ncoast!allbery@hal.cwru.edu
allberyb@skybridge.sdi.cwru.edu allbery@uunet.uu.net
comp.sources.misc is moving off ncoast -- please do NOT send submissions direct
Send comp.sources.misc submissions to comp-sources-misc@.