How to install mu and mu4e with GUI Emacs

Question

I've been using this guide to set up email in Emacs on macOS. I managed the offlineimap connection and replication into a Maildir. I installed mu with brew install mu:

$ which mu
/usr/local/bin/mu

But I cannot find anything in the Emacs site-lisp to launch mu4e:

$ ls /usr/local/share/emacs/site-lisp/mu/ ls: /usr/local/share/emacs/site-lisp/mu/: No such file or directory

But the website suggests that mu4e is installed:

mu includes an emacs-based e-mail client (mu4e)

I tried building from git and using brew in this way:

EMACS=$(which emacs) brew install mu --with-emacs --HEAD

and in both cases I get:

configure: error: Package requirements (gmime-3.0) were not met:

No package 'gmime-3.0' found

Consider adjusting the PKG_CONFIG_PATH environment variable if you
installed software in a non-standard prefix.

Alternatively, you may set the environment variables GMIME_CFLAGS
and GMIME_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

and this package is not in brew:

Error: No formulae found in taps.

Furthermore, on my home computer the command EMACS=$(which emacs) brew install mu --with-emacs --HEAD reinstalls emacs with brew, despite it being already installed.

Another attempt is to install mu, then just copy the mu4e files to site-lisp:

brew install mu
git clone git://github.com/djcb/mu.git
mkdir /usr/local/share/emacs/site-lisp/mu/
cp -r mu4e /usr/local/share/emacs/site-lisp/mu/

and adding this in ~/.emacs:

(require 'mu4e)
(add-to-list 'load-path "/usr/local/share/emacs/site-lisp/mu/mu4e")

But I get the error Cannot open load file: No such file or directory, mu4e-meta. And still, M-x mu4e doesn't work.

How can I install mu4e?

Answer 1

To get elisp files installed together with mu using brew in OSX, you need to run:

brew install mu

The available arguments to mu install is shown with brew info mu.

You can get the list of all installed files with brew ls --verbose mu. At the moment, the directory /usr/local/Cellar/mu/1.0/share/emacs/site-lisp/mu/mu4e/ gets symlinked to /usr/local/share/emacs/site-lisp/mu/mu4e.

The mu configuration in your emacs init file needs to first call add-to-list pointing to the directory where mu4e files are, followed by the form (require mu4e) and all other variable settings:

(add-to-list 'load-path "/usr/local/share/emacs/site-lisp/mu/mu4e")
(require 'mu4e)
 ...

If mu4e fails to start even after require'ing it, you should try adding (setq mu4e-mu-binary "/usr/local/bin/mu"). mu4e has tons more variables you can set to get the behavior you want.

Answer 2

I just got mu with mu4e installed on Mojave. Here are links to the problems associated with doing so on a Mac:

Cf for an explanation of the problem & hurdles:

1. "installing mu and mu4e with homebrew with emacs from emacsforosx" https://blog.danielgempesaw.com/post/43467552978/installing-mu-and-mu4e-with-homebrew-with-emacs

2. "A COMPLETE GUIDE TO EMAIL IN EMACS USING MU AND MU4E" http://cachestocaches.com/2017/3/complete-guide-email-emacs-using-mu-and-/

And, here is what worked for me:

1. In order to modify /usr/bin/emacs to prevent Homebrew from dropping the co-install of "mu4e", I had to disable the System Integrity Process: reboot + Cmd+R for recovery mode + 'Utilities' > Terminal & csrutil status && csrutil disable && reboot (to exit recovery mode)

2. Then, after moving /usr/bin/emacs to /usr/bin/emacs.bak, I symlinked a version of Emacs > 23.6 (I think that's the minimum version required by Homebrew to trigger an install of 'mu4e' along with mu) into /usr/bin (which is where Homebrew checks to see which version of Emacs is installed). See the above linked webpages for details.

3. Symlink an installed Emacs > 23.6 into /usr/bin

➜ ✗ sudo ln -s /Applications/Emacs1.app/Contents/MacOS/Emacs /usr/bin/emacs

4. Verify the symlink:

➜ ✗ ls -l /usr/bin/emacs lrwxr-xr-x 1 root wheel 45 Apr 12 17:04 /usr/bin/emacs -> /Applications/Emacs1.app/Contents/MacOS/Emacs

5. Install mu w/ mu4e (Already had Emacs-27.0.90 installed.)

➜ ✗ brew install mu --HEAD

This is what I had for mu & mu4e after the install:

➜ ✗ ls /usr/local/share/emacs/site-lisp/mu/mu4e

➜ ✗ ls -l /usr/local/share/emacs/site-lisp/mu/mu4e

6. Symlink 'mu' to /usr/local/bin

➜ ✗ ln -s /usr/local/Cellar/mu/HEAD-e9fb70e_1/bin/mu /usr/local/bin/

7. Verify the symlink.

➜ ✗ ls -l /usr/local/bin/mu /usr/local/bin/mu -> /usr/local/Cellar/mu/HEAD-e9fb70e_1/bin/mu

8. Verify the 'mu' symlink ➜ ✗ which mu /usr/local/bin/mu

9. Test 'mu' command-line use

➜ ✗ mu --version mu (mail indexer/searcher) version 1.3.10 Copyright (C) 2008-2020 Dirk-Jan C. Binnema License GPLv3+: GNU GPL version 3 or later http://gnu.org/licenses/gpl.html.

That's as far as I've gone with mu+mu4e. I haven't yet tested it in Emacs.

Good luck.

Answer 3

The advice of running brew ls mu is a great start but it'll get you a path that has a version number in it. E. g., [snip]/1.x.x/share/emacs/site-lisp/mu/mu4e. I am guessing this link goes bad if the version number changes after an update. That is why we need a symlink.

It seems that the symlink used to be at /usr/local/share/emacs/site-lisp/mu/mu4e but as many comments point out--that is no longer true. It is probably because the output to brew --prefix has changed from /usr/local. The symlink can always be reliably found by echo $(brew --prefix)/share/emacs/site-lisp/mu/mu4e. Try,

ls $(brew --prefix)/share/emacs/site-lisp/mu/mu4e

And you should see the elisp files.