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What timezone formats exists on UNIX systems? Can someone gather them in a short answer? How can I recognize them?

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In what context? – Stéphane Chazelas Oct 1 '12 at 15:01
olson, posix, what else? – gasko peter Oct 1 '12 at 15:05
Why are you trying to do this in the first place? Leave time zone parsing up to existing code. It's somewhat system-specfific, and time is a very deep and broad subject. If you implement whatever algorithm you're attempting based on a short answer, you will get the algorithm wrong, guaranteed. You will miss some corner case somewhere, which someone else has already covered in the existing code. – Warren Young Oct 1 '12 at 18:47
up vote 4 down vote accepted

Time zone data in modern UNIX systems comes from the public-domain IANA Time Zone Database. This database is what provides the timezone names, and the complex and ever-changing rules for timezones themselves. Wikipedia has a good overview of the database and the various formats in which it can be found, and includes a list of timezones from that database.

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I'm searching for timezone FORMATS, not timezones, ex.: OLSON, POSIX – gasko peter Oct 2 '12 at 8:11
Well, you just named them both. POSIX is insufficient to describe zones fully, and Olson is the guy who made the database I just mentioned. Everyone should use the Olson names from the tz database these days. – Jim Paris Oct 2 '12 at 18:15
By the way, the tz database also includes the POSIX names under the "SystemV" prefix. – Jim Paris Oct 2 '12 at 19:30

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