On Tue, Apr 25, 2017 at 01:14:26PM +0200, Michael Kerrisk (man-pages) wrote:
[...]
>        The file timestamps are structures of the following type:
> 
>            struct statx_timestamp {
>                __s64 tv_sec;    /* Seconds since the Epoch (UNIX time) */
>                __s32 tv_nsec;   /* Nanoseconds before or since tv_sec */
>            };

Nanoseconds since tv_sec.  The "before tv_sec" is not implemented yet
and I hope nobody is going to implement it for the reasons I mentioned
in https://marc.info/?i=20170422192743.GA17005%40altlinux.org


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ldv