Set all incoming emails as read with Mu4e

Last week I decided to make my Org Agenda even more my Emacs control room: now my emails appear directly as tasks in my agenda.

I already wrote about this in an older blog, where I do the same for Slack messages. The idea is that this decreases distraction and helps me feel in control of my async chats. I just repeated the same for emails, and I plan to share how you can do that in another blog.

Here I want to share a little Mu4e (my Emacs email client) trick: how to make all unread emails read using a single command. The reason I need this is that some mails are just noise and I need to discard them without opening them. When I mark them as DONE in the Org Agenda, they stay unread though! That is why I nead a "cleanup" functions that sets them all as read.

Anyway, if you ever need a similar bulk execution, this is the code:

(defun my/emails-set-all-as-read ()
  "Make all emails read."
  (interactive)
  (require 'mu4e-contrib)
  (with-temp-buffer
    (mu4e-headers-search-bookmark "flag:unread AND NOT flag:trashed")
    (sleep-for 0.15)
    (mu4e-headers-mark-all-unread-read)
    (mu4e-mark-execute-all 'no-confirmation)))

I mostly found out how to do that via this issue: https://github.com/djcb/mu/issues/128

Through that I discovered you can already mark all unread mails as read, by using mu4e-headers-mark-all-unread-read (that function belongs to the mu4e-contrib file). That works only within the header view (the buffer where emails are shown in Mu4e), so the search-bookmark and the sleep-for are to get there. mu4e-mark-execute-all is what executes the marking for us.

You can adapt this to something useful to you by changing "flag:unread AND NOT flag:trashed" which is the mu expression to filter for unread emails and the marking you need (you can mark emails for other things, like thrashing).

That's it, just a tiny bit of Elisp to save some of (my) time.

Happy emailing!