Eli Zaretskii wrote: > In C, you pass probe time_t values to the function localtime, until > you find the value for which the tm_isdst flag in the struct tm > returned by localtime changes from 0 to 1 or vice versa. > > In Lisp, we will need some Lisp binding to localtime or its sibling > functions, to do the same. Perhaps the iterative solution can be > coded in C, with only the result exposed to Lisp. > > Does this make sense? Apologies if I'm missing something.
No, this makes sense. I'm trying to say, this essentially is what cal-dst does already (see calendar-next-time-zone-transition) to find the dates when DST starts/ends. But it (essentially) just does it once, for the next year, then assumes that the result it gets applies to every year. I have presented a patch which makes it do this iterative check for every year, the first time it encounters a given year. It doesn't seem to take an appreciable amount of time, so I don't think it's necessary to rewrite it in C. _______________________________________________ emacs-pretest-bug mailing list emacs-pretest-bug@gnu.org http://lists.gnu.org/mailman/listinfo/emacs-pretest-bug
