Re: CLONE_FILES problem.

Matthias Urlichs (
Mon, 19 Aug 1996 13:18:46 +0200 (MET DST)


Alan Cox wrote:
>> structures are concerned. Something should probably be done with
>> blocking accesses to files, i.e. if one thread is read()ing from a file
>> descriptor which another wants to close, the first should get a signal or
>> something.
>Bumping the count as suggested elsewhere is a much more elegant, scalable
>and self locking answer.
Depends on what you want to do. For files at least, I'd want the file
descriptor to be closed, period. This means that if thread A reads from the
modem and thread B wants to close things down, thread B close()s the file
and A notices this somehow (EOF, signal, whatever).

Memory mappings can of course use counters, but you'd have to add the
appropriate unlock calls to every procedure which uses verify_area.
This is probably something that should have been done from the beginning...

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