Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!csd4.milw.wisc.edu!srcsip!nic.MR.NET!hal!ncoast!allbery
From: allbery@ncoast.ORG (Brandon S. Allbery)
Newsgroups: comp.unix.wizards
Subject: Re: getcwd() and friends.
Message-ID: <13563@ncoast.ORG>
Date: 13 Apr 89 20:27:05 GMT
References: <3675@ficc.uu.net> <14689@rpp386.Dallas.TX.US> <811@mtxinu.UUCP> <2001@unisoft.UUCP> <3746@ficc.uu.net>
Reply-To: allbery@ncoast.UUCP (Brandon S. Allbery)
Followup-To: comp.unix.wizards
Organization: Cleveland Public Access UN*X, Cleveland, Oh
Lines: 35

As quoted from <3746@ficc.uu.net> by peter@ficc.uu.net (Peter da Silva):
+---------------
| In article <2001@unisoft.UUCP>, greywolf@unisoft.UUCP (The Grey Wolf) writes:
| > if they were "instead of", and chmod() were eliminated so that only
| > fchmod remained, how would you change the mode of a file that was mode
| > 000?  You wouldn't be able to O_RDWR or O_EXEC the file/directory and
| > therefore couldn't gain a valid file descriptor to pass to fchmod().
| 
| How about O_TOKEN which returns a fd you can't do anything to until you
| do another open on it. Soirt of like an RMX file token or an AmigaDOS
| file lock. Have to call the fd version of open something other than
| fopen or fdopen, though.
| 
| This would make 'dup' into fd_open(fd, O_CLONE), where O_CLONE means
| 'same flags as the first fd'...
| 
| Do this cleverly enough and almost all the regular calls can actually use
| the new calls... you just need to keep 'open' around so you can get the
| fd in the first place:
+---------------

At the risk of being flamed for Political Incorrectness, I'll note that this
sounds vaguely familiar.

	open(path, O_TOKEN)	<------>	shmget(key)
	fd_open(token, ...)	<------>	shmat(shmid, ...)

I find myself wondering if AT&T knew what it was doing after all....

++Brandon
-- 
Brandon S. Allbery, moderator of comp.sources.misc	     allbery@ncoast.org
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