Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!purdue!haven!adm!xadmx!Arnold.Gill%QueensU.CA@qucdn.queensu.ca
From: Arnold.Gill%QueensU.CA@qucdn.queensu.ca
Newsgroups: comp.unix.questions
Subject: cal program on UNIX systems is wrong!!
Message-ID: <20492@adm.BRL.MIL>
Date: 4 Aug 89 02:29:47 GMT
Sender: news@adm.BRL.MIL
Lines: 34


     I have been exploring the UNIX system on our MIPS, and was playing around
with the `cal' routine.  Upon reading the manual, I found that the special
case stated in the manual, namely that in September, 1752 11 days were dropped
from the calendar is absolutely garbage!!

     Calendar reform did not occur as late as 1752, even in Britain and the
US.  Rather, calendar reform occurred nearly two centuries earlier when Pope
Gregory decreed that throughout Christendom, the day following October 4, 1582
would be October 15.  That's why we call our current calendar Gregorian!  If
you wish references to look this up, might I suggest the Astronomical Almanac,
published jointly by the US Naval Observatory and the Royal Greenwich
Observatory.  When counting Julian days in astronomical software, century
counts are listed evenly back to 1600, i.e. 11 days are NOT missing in the
18th century!

     Obviously, there was no astronomer around when this particular program
was written. :-)  (Astronomers seem to be the only people who really need to
keep an accurate track of time over centuries.)  I would suggest that this
little quirk be fixed up in some future release - it should really be a
trivial task.

     If anyone has comments on this issue, e-mail me directly - I do not read
this particular forum.

     On a side note, I would be interested in getting hold of the C source for
the following supposedly standard UNIX routines - which seem to be missing
from our MIPS:  (un)pack, (un)compress, whereis.  Thank you.  Again, if you
could e-mail these to me directly.

Arnold Gill
Queen's University at Kingston
BITNET:    gilla@qucdn
INTERNET:  Arnold.Gill@QueensU.CA