From: tuhs@cuzuco.com (Brian S Walden)
Subject: [TUHS] UNIX turns forty
Date: Thu, 21 May 2009 16:39:27 -0400 (EDT) [thread overview]
Message-ID: <200905212039.n4LKdRWd011261@cuzuco.com> (raw)
On 20 May 2009, at 05:56, Derek Peschel wrote:
> Interesting question! And related questions -- When did the current
> start of the epoch get chosen? Were there any false starts or early
> changes? (I seem to recall reading about one change, moving forward
> by a year.) And were there ever any dates in the system that couldn't
> be correctly recorded, because the epoch started too late?
The current epoch was choose for the 4th edition, the man page date
is 8/5/73. The first edition's epoch was 00:00:00, Jan. 1, 1971.
This can be obtained from the time(2) man page. Here they are parapharsed,
I like that epoch changed from the second to thrid editions, but the
man page date did not; and the "bugs" line from the 3rd edition is memorable.
v1:
DATE: 11/3/71
DESCRIPTION: time returns the time since 00:00:00, Jan. 1, 1971, measured in sixtieths of a second.
BUGS: The chronological-minded user will note that 2**32 slxtieths of a seeond is only about 2.5 years.
v2:
DATE: 3/15/72
DESCRIPTION: time returns the time since 00:00:00, Jan. 1, 1971, measured in sixtieths of a second.
BUGS: The chronological-minded user will note that 2**32 slxtieths of a seeond is only about 2.5 years.
v3:
DATE: 3/15/72
DESCRIPTION: time returns the time since 00:00:00, Jan. 1, 1972, measured in sixtieths of a second.
BUGS: The time is stored in 32 bits. This guarantees a crisis every 2.26 years.
v4:
DATE: 8/5/73
DESCRIPTION: time returns the time since 00:00:00 GMT, Jan. 1, 1970, measured in seconds.
next reply other threads:[~2009-05-21 20:39 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-05-21 20:39 Brian S Walden [this message]
-- strict thread matches above, loose matches on Subject: below --
2009-06-05 3:48 Brian S Walden
2009-06-05 4:18 ` Larry McVoy
2009-06-05 11:42 ` Jim Capp
2009-06-05 14:40 ` John Cowan
2009-06-05 16:06 ` Ian King
2009-06-05 18:29 ` John Cowan
2009-06-06 5:20 ` Ian King
2009-06-05 18:40 ` Jason Stevens
2009-05-19 4:42 Aharon Robbins
2009-05-19 6:13 ` Jason Stevens
2009-05-19 15:12 ` M. Warner Losh
2009-05-19 15:28 ` Michael Kerpan
2009-05-19 15:21 ` John Cowan
2009-05-15 16:48 Tim Newsham
2009-05-15 17:27 ` Jason Stevens
2009-05-15 18:09 ` Al Kossow
2009-05-19 2:20 ` Rafael R Obelheiro
2009-05-19 21:31 ` Warren Toomey
2009-05-19 21:49 ` John Cowan
2009-05-20 0:43 ` Jason Stevens
2009-05-20 4:56 ` Derek Peschel
2009-05-20 5:16 ` Jason Stevens
2009-05-20 8:21 ` Tim Bradshaw
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