cygwin sent the following at Friday, January 20, 2012 7:34 PM >I'm seeing a problem with my setup where the date command fails in an >odd way: > >this is what it does: $ date -d '1 January 1900' date: invalid date `1 >January 1900' > >same thing on a linux box: $ date -d '1 January 1900' Mon Jan 1 00:00:00 >PMT 1900 > >any dates after 1901 seem to work OK: $ date -d '1 January 1902' Wed Jan >1 00:00:00 PMT 1902 > >but nothing works before then: > >$ date -d 'today - 150 years' date: invalid date `today - 150 years' > >$ date -d 'today - 100 years' Sun Jan 21 01:33:27 WET 1912 > >this is the info for the date command: > >$ date --version date (GNU coreutils) 8.14 Packaged by Cygwin (8.14-1) >Copyright (C) 2011 Free Software Foundation, Inc. License GPLv3+: GNU >GPL version 3 or later <http://gnu.org/licenses/gpl.html>. This is >free software: you are free to change and redistribute it. There is NO >WARRANTY, to the extent permitted by law. > >Written by David MacKenzie. > >Where should I start debugging?
Start by finding out exactly when date stops working. The followijng is the same date version, everything up to date, on Windws 7: /c> date -d 1901-12-13\ 15:45:52 Fri, Dec 13, 1901 3:45:52 PM /c> date -d 1901-12-13\ 15:45:51 date: invalid date `1901-12-13 15:45:51' /c> date -d 1901-12-13\ 15:45:51.999 date: invalid date `1901-12-13 15:45:51.999' /c> date -d 1901-12-13\ 15:45:52.000 Fri, Dec 13, 1901 3:45:52 PM So 1901-12-13 15:45:52 is the earliest that works Waiting a few minutes and repeating does not change this. When is that in seconds: /c> date -d 1901-12-13\ 15:45:52 +%s -2147483648 %s give the number of "seconds since 1970-01-01 00:00:00 UTC". So this critical time is 2147483648 seconds before the start of the Unix epoch. Now -2147483648 = -2^31. So it looks like cygwin date encodes seconds as signed long integers. Presumably, date on your linux box was compiled to use something bigger. - Barry Disclaimer: Statements made herein are not made on behalf of NIAID. -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple
