Hi again, Timothy Sample <samp...@ngyro.com> writes:
> Hello, > > Ludovic Courtès <l...@gnu.org> writes: > >> Hi Ben, >> >> Ben Sturmfels <b...@sturm.com.au> skribis: >> >>> In Evolution though, all my calendar events show up in UTC time, so I >>> have appointments showing up at eg. 1am. >>> >>> When I go to Edit, Preferences, Calendar and Task, General, under >>> timezone it says: >>> >>> [x] Use system time (UTC) >> >> Could you figure out how Evolution determines what the current time zone >> is? >> >> Guix provides /etc/localtime, which is what libc functions use, but I’m >> guessing Evolution uses a custom framework, possibly involving a >> hard-to-believe network of D-Bus services. > > I just looked through the source code, and learned that it really, > really wants “/etc/localtime” to be a symlink, because it wants to > resolve which timezone alias the user is using, not just the data. If > it is not a symlink, it runs through a bunch of system specific checks > (looking up configuration files, etc.) and then tries to compare inodes > and finally file contents. I get why it wants the name and not just the > data, but I’m not sure why it tries to figure out the absolute canonical > source file for the timezone data instead of just taking the data from > “/etc/localtime”. > > It’s easy to patch “evolution-data-server”, but maybe we could do > better? It seems the “right” way to do what they are doing is to check > the “TZ” environment variable. However, we don’t set that anymore > because it causes problems with setuid programs > (cf. <https://bugs.gnu.org/29212>). We have a comment that says that > “TZ” is unnecessary, but it actually has a bit more information than > just having data in “/etc/localtime”, since it could be the name of a > timezone alias. A small improvement might be to make “/etc/localtime” a > symlink, but that might run into the same issues described the bug. Okay, so it turns I don’t know what “TZ” is! :p It does not contain the timezone name, like “America/New_York”, but rather its designation, like “EST”. What “evolution-data-server” wants is the name. > I’ve noticed a few other problems with timezones in the GNOME ecosystem, > which is why I was curious about this. Perhaps they all have a common > root cause. > > I’m happy to patch this as stop-gap measure, but is there some way we > could “do the right thing” here? I guess there is no standard way to get the name of the system timezone, and that is why “evolution-data-server” goes to such great lengths to figure it out. Sorry for the noise! -- Tim
