Author Archives: Ben Maughan

Using email address lists in mu4e

To set up lists of multiple email multiple recipients with mu4e, you can make use of mail aliases. To do this, add lists to a file with the following format, with the word “alias” followed by the name you want for the list, followed by a space-separated list of email addresses:

alias jsmiths "John Q. Smith <>" "Jane Q. Smith <>"

You can either save this file as ~/.mailrc or put it anywhere and tell Emacs where to find it using e.g.

;;mail aliases for lists (address lists)
(setq mail-personal-alias-file (expand-file-name "/homeb/bjm/docs/mail-aliases"))

Now, when composing an email you can type the alias (“jsmiths” in our example) and hit space, and it will expand to the list of email addresses.

If you are using my improved address completion, then you can add those aliases to your bjm/contact-file to have them appear in your completion lists.

Make Emacs a bit quieter

The minibuffer is the area at the bottom of your Emacs frame where you interact with Emacs prompts, or type commands. It also doubles up as the echo area, where Emacs tells you useful things. However sometimes when Emacs is prompting me for an answer in the minibuffer, the prompt is hidden by a message so I can’t see what I’m being asked any more.

When this happens, I found it is almost always a message about a buffer being reverted or a file being auto-saved. These messages can be prevented from appearing in the echo area as follows.

The revert messages are easy to silence with the following setting:

;; turn off auto revert messages
(setq auto-revert-verbose nil)

For the auto-save messages, it is a bit trickier. Some solutions suggest advising do-auto-save which is the function that does the actual job of auto-saving (e.g. this stackexchange question). However, this doesn’t work for Emacs 24.4 and newer since the call to do-auto-save bypasses the advice, for technical reasons I don’t fully understand!

A work around is to switch off the built-in auto-save, and replace it with our own silent version:

;; custom autosave to suppress messages
;; For some reason `do-auto-save' doesn't work if called manually
;; after switching off the default autosave altogether. Instead set
;; to a long timeout so it is not called.
(setq auto-save-timeout 99999)

;; Set up my timer
(defvar bjm/auto-save-timer nil
  "Timer to run `bjm/auto-save-silent'")

;; Auto-save every 5 seconds of idle time
(defvar bjm/auto-save-interval 5
  "How often in seconds of idle time to auto-save with `bjm/auto-save-silent'")

;; Function to auto save files silently
(defun bjm/auto-save-silent ()
  "Auto-save all buffers silently"
  (do-auto-save t))

;; Start new timer
(setq bjm/auto-save-timer
      (run-with-idle-timer 0 bjm/auto-save-interval 'bjm/auto-save-silent))

Note that I found some strange behaviour that do-auto-save does not work if the built-in auto-save is switched off altogether using (setq auto-save-default nil), so instead I had to set it for a long timeout to prevent it from running.

Automatically revert buffers

If you want Emacs to automatically update a buffer if a file changes on disk, then add the following to your emacs config file

;; auto revert mode
(global-auto-revert-mode 1)

Of course, if your buffer has unsaved changes when the file changes on disk, then Emacs will prompt you and your changes won’t be lost.

This mode only applies to buffers associated with files on the disk, but I like to have my dired view updated if the contents of a directory change. This is accomplished with the following code:

;; auto refresh dired when file changes
(add-hook 'dired-mode-hook 'auto-revert-mode)

Speedy sorting in dired with dired-quick-sort

The package dired-quick-sort gives you a pop-up menu with lots of useful options to sort your dired view by name, time, size and extension, and optionally group all of the directories together at the top of the listing. This can be a bit fiddly and dired-quick-sort makes it really easy.

Install the package with

(use-package dired-quick-sort
  :ensure t

and then hit S in a dired buffer to bring up the sorting menu. Your sorting choice is then remembered for new dired buffers.

Export org-mode headlines to separate files

I was recently managing a set of interviews and I had my notes on all of the candidates in a single org file, with each candidate under their own top-level headline:

* J Kepler
 - Nice work on orbits

* I Newton
 - Versatile
 - Hard to work with

* C Sagan
 - Good communication skills

However, I wanted to generate a separate pdf file for each candidate that I could circulate to interviewers (since each interviewer was only interviewing a subset of applicants).

I came across this stackexchange answer that demonstrated how to build a function to export top level headlines to separate files. There are a few variations on that page, and I put together the slightly tweaked version below. All of the credit goes to stackexchange user itsjeyd for a very detailed answer. In my version I hard code it to export to pdf, save the file first, and apply the export options from the parent file to each of the new files that are created. The new files have a name taken from the headline, with spaces replaced by underscores, unless the :EXPORT_FILE_NAME: property is set for a headline.

;; export headlines to separate files
(defun org-export-headlines-to-pdf ()
  "Export all subtrees that are *not* tagged with :noexport: to
separate files.

Subtrees that do not have the :EXPORT_FILE_NAME: property set
are exported to a filename derived from the headline text."
  (let ((modifiedp (buffer-modified-p)))
      (goto-char (point-min))
      (goto-char (re-search-forward "^*"))
      (set-mark (line-beginning-position))
      (goto-char (point-max))
       (lambda ()
         (let ((export-file (org-entry-get (point) "EXPORT_FILE_NAME")))
           (unless export-file
              (replace-regexp-in-string " " "_" (nth 4 (org-heading-components)))))
           (org-latex-export-to-pdf nil t)
           (unless export-file (org-delete-property "EXPORT_FILE_NAME"))
           (set-buffer-modified-p modifiedp)))
       "-noexport" 'region-start-level))))

Add multiple cursors with mouse clicks

I’ve written before about the wonderful multiple-cursors package. Usually I use it by hitting M-. (defined using the setup below) to fire off multiple cursors on successive lines or on successive occurrences of the current string (if some text is selected). I also use M-, if I want to remove some of those cursors. This covers 99% of my use of multiple cursors.

However, occasionally, the best way to get the cursors where you want them is with the mouse. With the following code, C-S-<left mouse click> adds a new cursor.

(use-package multiple-cursors
  :ensure t
  :bind (("M-." . mc/mark-next-like-this)
         ("M-," . mc/unmark-next-like-this)
         ("C-S-<mouse-1>" . mc/add-cursor-on-click)))

Some useful mu4e shortcuts

I wrote recently about setting up a custom key map, and there are a couple of shortcuts for mu4e functions that I use very often with that key map.

With the following code I define c in my key map to compose a new email. Since I previously set C-1 to be the prefix for my map, then C-1 c is the full keybinding. This works globally so I can start a new email from anywhere in Emacs with C-1 c.

I then supercharge the keybinding by using it to add a CC to an email if I am already composing one. This is done by binding C-1 c in the mu4e-compose-mode-map to message-goto-cc. So now C-1 c starts a new email unless I am already writing an email in which case it adds a CC instead.

While I am at it, I also add s to my keymap for mu4e-headers-search so I can use C-1 s to launch a search of my emails from anywhere in Emacs.

;; bjm-map is already  bound to the prefix C-1
;; use C-1 c to compose a new email
(define-key bjm-map (kbd "c") 'mu4e-compose-new)
;; use C-1 c for add cc if already in composition mode
(define-key mu4e-compose-mode-map (kbd "C-1 c") 'message-goto-cc)
;; add search
(define-key bjm-map (kbd "s") 'mu4e-headers-search)

Batch-edit file permissions in dired

I’ve written before about using the editing features in dired (AKA wdired) to do neat things like redirect symlinks. I recently discovered that by adding the following option to your emacs config file:

;; allow editing file permissions
(setq wdired-allow-to-change-permissions t)

then you can also edit the file permissions directly in the dired buffer.

Here’s a quick animated example where I want to set group write permissions for all the pdf files in a particular directory. I use several tools to make this really easy:

  1. I used dired-narrow to filter the view down to just the pdf files
  2. I use C-x C-q to make the dired buffer editable
  3. I move to the group write permission spot on the first line and then use multiple cursors to add a cursor for each line
  4. I hit w to set the write permission, RET to quit multiple cursors, and C-c C-c to make the change permanent


Customise the reply quote string in mu4e

You know the bit of text that appears before the quoted email when you reply to someone? Of course you can customise this in mu4e. By default a quoted reply will be preceded with something like

"On Mon, 30 Jan 2017, Joe Bloggs wrote:"

I wanted to include the time and email address of the sender, so I customised the variable message-citation-line-format as follows

;; customize the reply-quote-string
(setq message-citation-line-format "On %a %d %b %Y at %R, %f wrote:\n")
;; choose to use the formatted string
(setq message-citation-line-function 'message-insert-formatted-citation-line)

which translates to something like this

On Mon 30 Jan 2017 at 19:17, Joe Bloggs <> wrote:

The formatting options can be found by looking up the help for the variable with C-h v message-citation-line-format.

Sadly, this change broke my function to extract the sender name for my email template. Here is an updated version:

;; function to return first name of email recipients
;; used by yasnippet
;; inspired by
(defun bjm/mu4e-get-names-for-yasnippet ()
  "Return comma separated string of names for an email"
  (let ((email-name "") str email-string email-list email-name2 tmpname)
      (goto-char (point-min))
      ;; first line in email could be some hidden line containing NO to field
      (setq str (buffer-substring-no-properties (point-min) (point-max))))
    ;; take name from TO field - match series of names
    (when (string-match "^To: \"?\\(.+\\)" str)
      (setq email-string (match-string 1 str)))
    ;;split to list by comma
    (setq email-list (split-string email-string " *, *"))
    ;;loop over emails
    (dolist (tmpstr email-list)
      ;;get first word of email string
      (setq tmpname (car (split-string tmpstr " ")))
      ;;remove whitespace or ""
      (setq tmpname (replace-regexp-in-string "[ \"]" "" tmpname))
      ;;join to string
      (setq email-name
            (concat email-name ", " tmpname)))
    ;;remove initial comma
    (setq email-name (replace-regexp-in-string "^, " "" email-name))

    ;;see if we want to use the name in the FROM field
    ;;get name in FROM field if available, but only if there is only
    ;;one name in TO field
    (if (< (length email-list) 2)
        (when (string-match "^On.+, \\([^ ,\n]+\\).+wrote:$" str)
            (setq email-name2 (match-string 1 str))
            ;;prefer name in FROM field if TO field has "@"
            (when (string-match "@" email-name)
              (setq email-name email-name2))