Re: Time not representable

[Paul Eggert]

Following up on this, I just now committed a change
(bzr 103643) that should fix the problems noted in this
thread for time stamp overflow.  (This may require
minor changes to Windows makefiles to capture new
dependencies, but it shouldn't break Windows builds.)

I'd also like to fix the time stamp resolution problems
by adding more information to the output of current-time
and similar functions.  For example, if the time is
2011-03-13 06:47:51.191380874 UTC, (current-time) currently
yields (19836 26775 191380), losing the bottom 3 digits.
I'd like to change it to yield (19836 26775 191380 874000)
so that no information is lost.  That is, I'd like to
extend the time stamp format to have a picoseconds count
(in addition to the current microseconds count) on hosts
that have higher-resolution time stamps.  No host currently
keeps time to picosecond resolution, but many do track
nanoseconds so the extended format will be a win.

This change would affect all functions that use these
internal time stamps, namely float-time, format-time-string,
decode-time, current-time-string, current-time-zone,
set-file-times, current-time, file-attributes,
encode-time, and visited-file-modtime.  Current-format
internal time stamps would continue to work.