[tor-dev] New Fallback Directory File Format

[Damian Johnson]

> Done!
>
> * the file now starts with a type and a version line:
>   /* type=fallback */
>   /* version=2.0.0 */
> * extrainfo is mandatory (occasionally we won't get a descriptor, so
>   we'll warn and mark the relay extrainfo=0)
> * each fallback entry ends with /* ===== */

Sweet, thanks Tim!

> * is 6 extra info caches (up from 4) enough in a list of 150?

Hmmm. Can't say on Stem's side I have an opinion on this. It doesn't
rely on fallback directories for anything so extrainfo caches aren't a
concern.

> * do you want the delimiter before the first fallback entry as well?

Stem doesn't care about a delimiter before the first entry but that
seems like a good idea so we have a clear separation between comments
and the start of the machine readable section.

A detail Stem does care about is that the last entry ends with a
delimiter. If it doesn't that's fine, but code is a tad simpler if we
ensure it does. :)

Cheers! -Damian