http://man7.org/linux/man-pages/man2/utimensat.2.html If both tv_nsec fields are specified as UTIME_OMIT, then no file ownership or permission checks are performed, and the file timestamps are not modified, but other error conditions may still be detected. fs/utimes.c /* Nothing to do, we must not even check the path. */ if (tstimes[0].tv_nsec == UTIME_OMIT && tstimes[1].tv_nsec == UTIME_OMIT) return 0; if you're intending to match POSIX, the current text is correct. they say "If both tv_nsec fields are set to UTIME_OMIT, no ownership or permissions check shall be performed for the file, but other error conditions may still be detected (including [EACCES] errors related to the path prefix)." (http://pubs.opengroup.org/onlinepubs/9699919799/functions/futimens.html) but as the snippet above shows, the kernel doesn't, and so will silently return success even for a non-existent file if both times are UTIME_OMIT. i'm not sure why the kernel says "must", but even if they fix that, it would be useful for the man page to mention this subtlety. something like "(Note that at present the kernel performs no checks in this case, not even that the file exists, and will always return success.)". (strictly that's not true because the EFAULT check for the struct timespec* will have happened, but it seems less clear to try to include that fact.) --elliott -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
