As an online alternative to enh's option, https://nodatime.org/tzvalidate/generate can be used to generate a tzvalidate format report. The version can be specified as a query parameter, along with the zone, start year and end year. For example:

https://nodatime.org/tzvalidate/generate?version=2025a&zone=Asia/Tehran&startYear=1976&endYear=1982 (I've extended the year range there just for clarity)

That generates:

Asia/Tehran
Initially:           +03:30:00 standard +0330
1977-03-21 19:30:00Z +04:30:00 daylight +0430
1977-10-20 19:30:00Z +04:00:00 standard +04
1978-03-24 20:00:00Z +05:00:00 daylight +05
1978-08-04 20:00:00Z +04:00:00 standard +04
1978-12-31 20:00:00Z +03:30:00 standard +0330
1979-05-26 20:30:00Z +04:30:00 daylight +0430
1979-09-18 19:30:00Z +03:30:00 standard +0330
1980-03-20 20:30:00Z +04:30:00 daylight +0430
1980-09-22 19:30:00Z +03:30:00 standard +0330

(A quick scan suggests that's the same data as produced by zdump, which is certainly what I'd expect...)

On Tue, 18 Mar 2025 at 11:13, Roozbeh Pournader via tz <tz@iana.org> wrote:

Can someone please kindly give me a dump of Asia/Tehran changes according to the latest tzdata for the years 1977-1981?

I'm trying to piece together the newspaper bits and pieces and compare with the tz database, and it seems that there is clearly some transitions missing. Specifically, I find the following lines confusing:

    4:00    Iran %z 1979

    3:30    Iran %z

Does that mean we think Iran switched from UTC+4:00 to UTC+3:30 on Jan 1, 1979?

Thanks a lot,

Roozbeh