struct stat.h with nanosecond resolution

[Roland McGrath]

> Yes.  Also, GNU applications like Make and Coreutils currently check
> for "st_mtim.tv_nsec" when configuring support for nanosecond
> resolution, so it will make it a bit easier on the GNU app developers
> if glibc uses the name "st_mtim" as well.

Good enough for me.  In fact, it's easy enough to provide multiple aliases
(either by #define or anonymous unions) just to make more existing
applications that work on either Solaris or BSD happy.

> The BSD name "st_mtimespec" is news to me.  I guess GNU apps will have
> to learn about it at some point.

I think it's been that way in BSD for a good long while now.