Will C-based operating systems still be around in 30 years?
Who knows?  (^&  I was amused to be directed to the old
Tannenbaum/Torveld debate about MINIX and LINUX.  Predictions
about the demise of the i386 line and the doom of monolithic
UNIX-like systems proved to be greatly exaggerated.

Will {int} be 64-bit by that time?  If so, wouldn't {time_t}
come along for the ride?  (Technologically, at least a 64-bit
{int} for common systems doesn't seem hard to swallow, if one looks
back 30 years.  The TRS-80 with 4K ROM, 4K RAM debuted around 1976
or 1978; I think that it would be safe to call the Z80 CPU in it
an 8-bit CPU...)

As for negative dates, it seems desirable to be able to
represent times before the UNIX epoch.  The epoch isn't
*that* old yet.  (Though I would readily agree that if
you are really talking about historic context, a 32-bit
``seconds'' counter isn't going to be adequate anyway.)


-- 
  "I probably don't know what I'm talking about."  http://www.olib.org/~rkr/