> I use a C wrapper to do the same (with date prefixes like 2014-05-09
> (Fri) 12:47:19) -- I originally did it to do argument conversions
> around .. to have date-based searches before those came to notmuch
> (and I am still using it, as I don't have to type date: prefix)

Having a wrapper script possible, however, it is quite a hack and
doesn't potentially collect everything. There's already a
.notmuch-config file, so adding a logging directive should be
straightforward. It's more about whether something like this becomes
part of notmuch directly.

>> Would be nice to be able to log all operations done via libnotmuch
>> too though.
>
> IIRC someone suggested/asked whether we'd get logs where all
> Message-ID:s affected were logged. That could be useful (and produce
> lot of log when one does notmuch tag +foobar '*')

I'm not worried about the size of the logfiles. Drives are large and
many utilities exist to create a rolling removal and compression of log
files.

  Sebastian