I periodically have to kill and restart my X server when it freezes. I probably have the wrong configuration, since it starts off in low-graphics mode until I manually restart the graphical login manager (I’m using sddm). Anyway, since it’s been hard to debug and fix that issue, I figured I’d address the part that really bugs me when I restart X: dealing with ungraceful Emacs exits.
M-x recover-session does a decent job of restoring my modified files and I usually remember to call it from the scratch screen, but sometimes I forget, and then I end up losing changes.
I started taking advantage of the fact that I used
(server-start) to enable other Emacs clients to connect to the same process. Whenever I needed to restart X, I’d first switch to a console, use
emacsclient -c to connect to Emacs, and use
M-x save-buffers-kill-emacs to close my Emacs neatly. Still, starting my Emacs from X meant that I had to restart Emacs each time I restarted X.
It turns out that you can run Emacs as a background process with
emacs --daemon and then connect to it with
emacsclient -c. When I did that, though, the emacsclient frame didn’t have my color theme applied. This
after-make-frame-functions addition fixes that:
(defun my/setup-color-theme () (interactive) (color-theme-solarized-dark) (set-face-foreground 'secondary-selection "darkblue") (set-face-background 'secondary-selection "lightblue") (set-face-background 'font-lock-doc-face "black") (set-face-foreground 'font-lock-doc-face "wheat") (set-face-background 'font-lock-string-face "black") (set-face-foreground 'org-todo "green") (set-face-background 'org-todo "black")) (add-hook 'after-make-frame-functions (lambda (frame) (select-frame frame) (my/setup-color-theme)))
Once I got
emacs --daemon and
emacsclient -c working to my satisfaction, I decided to go one step further and get it to run automatically when I start my computer. I tried the init script at https://www.emacswiki.org/emacs/EmacsAsDaemon . My Linux install uses systemd, so enabling the init script resulted in a message about a missing service file. I removed the init script and created this
[Unit] Description=Emacs: the extensible, self-documenting text editor [Service] Type=forking ExecStart=/usr/local/bin/emacs --daemon ExecStop=/usr/local/bin/emacsclient --eval "(progn (setq kill-emacs-hook 'nil) (kill-emacs))" Restart=always TimeoutStartSec=0 [Install] WantedBy=default.target
and then I ran these commands as my regular user account:
systemctl --user enable emacs systemctl --user start emacs
Then I changed the
emacs in my
emacsclient -c, so that a new X session would connect to the existing session instead of starting a new one. That way, Emacs automatically started as my user whenever I restarted the computer, and I connected to that process when I started X.
Still, restarting X caused the Emacs daemon to crash. This is a GTK-related bug which
emacs --daemon warns you about. I recompiled Emacs using
./configure --with-x-toolkit=lucid; make; make install. It seems to work fine now; I can ungracefully restart X, and my Emacs stays the same. Bonus: because Emacs gets initialized when I start my computer and all I need to do is connect to that process, when I log in, it feels like Emacs starts up really quickly.
Final touches: I noticed that TRAMP couldn’t find my SSH keyring, so it got stuck waiting for my passphrase when I tried running remote scripts in Org Babel like so:
#+begin_src sh :dir [email protected]:~ perl library-new.pl Business #+end_src
Because my SSH socket looks like
/tmp/ssh-BLAHBLAHBLAH/agent.PROCESSID, the SSH_AUTH_SOCK setting (Environment=SSH_AUTH_SOCK=%t/keyring/ssh) described on EmacsWiki didn’t work for me. This snippet from https://github.com/nhoffman/.emacs.d/blob/master/init.org worked, though.
(defun my/ssh-refresh () "Reset the environment variable SSH_AUTH_SOCK" (interactive) (let (ssh-auth-sock-old (getenv "SSH_AUTH_SOCK")) (setenv "SSH_AUTH_SOCK" (car (split-string (shell-command-to-string "ls -t $(find /tmp/ssh-* -user $USER -name 'agent.*' 2> /dev/null)")))) (message (format "SSH_AUTH_SOCK %s --> %s" ssh-auth-sock-old (getenv "SSH_AUTH_SOCK"))))) (my/ssh-refresh)
emacs --daemon didn’t pick up the default browser I’d configured in KDE. Opening URL links from Org Mode started a separate Chromium process instead of using Google Chrome. I fixed that by switching from
browse-url-generic, like so:
(setq browse-url-generic-program "google-chrome") (setq browse-url-browser-function 'browse-url-generic)
Let’s see how this works!