Thanks for the quick response! > [..] but we should start with the actual POSIX spec under TZ Yes, that is exactly what I meant: Newlib supporting the <> (angle brackets) syntax. I didn't know that it was actually part of POSIX spec, since so many libs actually don't implement it. > The BSD or TZcode implementations could probably be adapted [..] It looks like the TZcode implementation by Paul Eggert uses a different approach to parsing the strings, than the current implementation in newlib (https://sourceware.org/git/?p=newlib-cygwin.git;a=blob;f=newlib/libc/time/tzset_r.c). I'm not sure, if you want to copy the code over or use changes by e.g. Earle F. Philhower from https://github.com/earlephilhower/newlib-xtensa/pull/14. Because of the above question, I'm not sure how to continue on this. I would like to contribute myself and submit an implementation, but I'll wait for feedback by other maintainers, first. Cheers ------------ jdoubleu