getcwd() and friends.

[Brandon S. Allbery]

As quoted from <3746 at ficc.uu.net> by peter at ficc.uu.net (Peter da Silva):
+---------------
| In article <2001 at unisoft.UUCP>, greywolf at 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 at ncoast.org
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