Re: calendar gets wrong end for Daylight Savings Time

[Eli Zaretskii]

> Cc: address@hidden,  address@hidden,  address@hidden,
>         address@hidden
> From: address@hidden (Kim F. Storm)
> Date: Wed, 08 Nov 2006 10:22:25 +0100
> >
> > I don't think Emacs needs to consult tzdata, because on system that
> > have it, the library functions which handle time, such as mktime,
> > already consult that data base.  So the times you get from the library
> > are already correctly taking into account the DST settings for the
> > correct year.
> 
> But it's not just a matter of whether DST applies to the current time & date.

I didn't say ``current''.  mktime and friends consult the tzdata
database for _any_ time_t value.

> I would assume that M-x calendar must use the database directly to
> find out _when_ DST starts and ends to print the calendar correctly.

It can do that, but it doesn't have to: it could alternatively pass
the corresponding time_t value to the time routines and get the DST
flag back as the result.  The Lisp primitives that return the current
time or time string should support that already.