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@xxxxxx> http://mj.ucw.cz/ Faculty of Math and Physics, Charles University, Prague, Czech Rep., Earth Mr. Worf, scan that ship." "Aye, Captain... 600 DPI? -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html