Emacs daemon preventing correct operation of saveplace

Question

Writes to saveplace are not persisting after the emacs daemon stops.

Saveplace is configured in my init file as:

;; saveplace remembers your location in a file when saving files
(use-package saveplace
  :config
  (setq save-place-file (expand-file-name "saveplace" savefile-dir))
  ;; activate it for all buffers
  (save-place-mode t))

I'm using systemd for the emacs daemon:

[Unit]
Description=Emacs text editor
Documentation=info:emacs man:emacs(1) https://gnu.org/software/emacs/

[Service]
Type=simple
ExecStart=/usr/bin/emacs --fg-daemon
ExecStop=/usr/bin/emacsclient --eval "(kill-emacs)"
Environment=SSH_AUTH_SOCK=%t/keyring/ssh
Restart=on-failure

[Install]
WantedBy=default.target

When I run kill-emacs or save-buffers-kill-emacs and then query the contents of saveplace, its contents accurately reflect the last cursor position in each buffer. However, if I then run $ systemctl --user restart emacs, the file reverts to the contents it had before the last emacs session. If I open saveplace in vim and write the file contents before restarting, they persist past the daemon restart. So, I thought it might be an issue with the buffers not flushing, but if I run $ sync saveplace and then restart the daemon, the correct contents do not persist.

What's going wrong here and how do I fix it?

Answer 1

I fixed this by changing ExecStart in the systemd service file to:

ExecStart=/usr/bin/emacs --daemon

--daemon is equivalent to --bg-daemon, which starts the emacs daemon in the background (disconnects it from a terminal). I'm still unclear on why this works, however.

Answer 2

Untested, but this might be why:

(defun save-place--setup-hooks (add)
  [...]
    (unless noninteractive
      (add-hook 'kill-emacs-hook #'save-place-kill-emacs-hook))

Presumably save-place.el doesn't think it's OK for that hook to happen in a non-interactive context.

If you disagree, you could add the hook in your own init code after enabling the mode, and see how you get on?