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SubjectRe: file offset corruption on 32-bit machines?
Hello!

> [*] file_pos_{read,write} (fs/read_write.c) are not called under lock (in
> sys_read, sys_write, ...), so even if f_pos is written atomically, you will
> be able to get races when accessing shared descriptor from different threads.

There are however cases when such behavior is perfectly valid: For example
you can have a file of records of a fixed size, whose order does not matter.
Then multiple processes can produce the records in parallel, sharing
a single fd.

> I think that POSIX states, that behavior is undefined under these conditions.

Do you have a pointer to that?

Have a nice fortnight
--
Martin `MJ' Mares <mj@ucw.cz> http://mj.ucw.cz/
Faculty of Math and Physics, Charles University, Prague, Czech Rep., Earth
Mr. Worf, scan that ship." "Aye, Captain... 600 DPI?


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