Date: Fri, 17 Feb 2006 17:59:00 +0530 From: "N. Raghavendra" <raghu@mri.ernet.in> Message-ID: <86hd6ynp83.fsf@riemann.mri.ernet.in> | By `tzfile', I meant precisely the binary files produced by `zic', and | documented in tzfile(5). I am now able to unpack the binary files | correctly into Lisp objects. Next, I should interpret the unpacked | data properly. OK, that wasn't clear. If you're working with the binary file, then ado's reply is the one you should take notice of. All you need to do is find the transitions in that file that are immediately before, and after, the time you start with - the one before then tells you the timezone offset, name, ... The one after is needed just so you are sure you have found the correct "before". The only complication is if you're trying to handle times into the far future - when all anyone can do is guess at what the rules will be. If you want to accept the timezone's project's guesses (which really just assume that the current rules will not change - which means that they are almost certainly wrong) then you need to extrapolate from the data at the end of the file. That is where knowing what the rules actually say is useful (and where you might hare about the standard vs wall-clock vs UTC indications). Otherwise, those things, as ado's reply said, are simply irrelevant to you. Jesper's reply was assuming that you (or someone) was reading the source (tzdata) files. kre