Bob Proulx writes: > date -d '1991-04-14 12:00 +1 day' > > > I'm from china by the way, and the time zone I am in and to which > > the systems were set is GMT8(or CST, China Standard Time).
Indeed, TZ=Asia/Shanghai date -d '4/14/1991' date: invalid date `4/14/1991' TZ=Asia/Shanghai date -d '4/14/1991 01:00:00' Sun Apr 14 01:00:00 CDT 1991 TZ=Asia/Shanghai date -d '1/1/1970 GMT + 671558399 sec' Sat Apr 13 23:59:59 CST 1991 TZ=Asia/Shanghai date -d '1/1/1970 GMT + 671558400 sec' Sun Apr 14 01:00:00 CDT 1991 According to tzdata, China had DST from 1986 to 1991. This comment in the source file indicates some doubt about correctness: # From Paul Eggert (2006-03-22): # Shanks & Pottenger write that China (except for Hong Kong and Macau) # has had a single time zone since 1980 May 1, observing summer DST # from 1986 through 1991; this contradicts Devine's # note about Time magazine, though apparently _something_ happened in 1986. # Go with Shanks & Pottenger for now. I made up names for the other # pre-1980 time zones. Maybe someone who can read Chinese could clear it up by finding the original policy declarations... > Please review the FAQ for date. > > http://www.gnu.org/software/coreutils/faq/#The-date-command-is-not-work= > ing-right_002e There might be less occurrences of this misunderstanding if we could teach date that -d 4/14/1991 is not actually a request for 4/14/1991 00:00:00, but "any time that existed during the day 4/14/1991", or perhaps a more specific "the first second of 4/14/1991". Has that been considered and rejected already, or is it just waiting for someone to implement it?
