* Paul Eggert:
On 2024-05-02 01:10, Jonathan Wakely via tz wrote:
I mean glibc code such as: https://sourceware.org/git/?p=glibc.git;a=blob;f=time/tzfile.c;h=41475399643... The comment says it's finding the offsets, but it seems to be finding the abbreviations for the first two transitions, storing them in the __tzname array.
That code is present for a different reason. It's trying to support obsolescent (but POSIX-required) variables like tzname, which in general make no sense when TZif files are used. (The next POSIX draft tries to fix this, but it's messed up, and I haven't had time to interact with the POSIX committee to clean things up.)
These obsolescent compatibility variables are not related to the question of what is the proper abbreviation to use for timestamps in 1908.
Unfortunately, __tzname is also used internally to ferry around information, see __tz_compute and the way it uses that to set tm_zone. We should not be doing that, but it's the code we currently have. 8-( Thanks, Florian