[tz] [musl] Re: Weird PST8PDT and EST5EDT behavior on Alpine Linux

[Russ Allbery]

Guy Harris <gharris at sonic.net> writes:
> On Mar 5, 2024, at 12:56 PM, Russ Allbery via tz <tz at iana.org> wrote:

>> but for the record, PST8PDT was for support for very old commercial
>> UNIXes where I believe that was the only recognized style of TZ
>> setting, and I'm pretty dubious that the POSIX-introduced :PST8PDT
>> syntax would work there.

> That TZ syntax dates back at least to System III:

> 	http://www.bitsavers.org/pdf/att/unix/System_III/UNIX_Users_Manual_Release_3_Jun80.pdf

> (see CTIME(3C)), which did not support anything tzdb-related, and didn't
> even support the more elaborate POSIX TZ syntax to include rules.

I don't see any reference to the leading colon in that documentation.  Am
I just missing something?  It seems to support what I said: PST8PDT was
supported, but :PST8PDT was not.

    If an environment variable named TZ is present, asctime uses the
    contents of the variable to override the default time zone. The value
    of TZ must be a three-letter time zone name, followed by a number
    representing the difference between local time and Greenwich time in
    hours, followed by an optional three-letter name for a daylight time
    zone. For example, the setting for New Jersey would be EST5EDT.

-- 
Russ Allbery (eagle at eyrie.org)             <https://www.eyrie.org/~eagle/>