How can I open a long list of files from within emacs

Question

I have a long list of files (full path names, one each on its own line, in a text file), and I want to open all of these files into emacs buffers, so that I can then use multi-occur-in-matching-buffers to navigate around in these files.

How can I open the list of files from within emacs ? The files listed are in arbitrary folders and have arbitrary file names. Ie., there is no regular pattern to the paths and names, so I am not looking for a particular regular expression to match my example below.

I don't want to do this at the emacs command line invocation, as I am running emacs on windows by clicking on an icon, and also, I want to keep open the other buffers (files) I have already open.

I am able to create a custom elisp function (hard-coding of the list of file names in the function), as follows (short example).

(defun open-my-files ()
  "Open my files"
  (interactive)
  (find-file "c:/files/file1.txt")
  (find-file "c:/more_files/deeper/log.log")
  (find-file "c:/one_last_note.ini")
)

I can place that elisp in a buffer, then select it all, then eval-region, then execute the function with M-x open-my-files.

However, it would be much more productive for me if the elisp would read the list of files from the text file which contains the list.

`C-x C-f "c:/files/file*.txt*"` Or if you are in that directory just `C-x C-f "file*.txt*"` — Drew, Jan 09 '19 at 20:07
Sorry, In elisp example solution, I showed 3 files in the same folder, but the long file list contains files from arbitrary folders. Ie., it's a long itemized list, and the file names are also arbitrary. I was just proving that I can do this as an elisp function, albeit with editing required. — MitchN, Jan 10 '19 at 00:39
Agreed. I edited the question to try to make it more clear now. Thx. — MitchN, Jan 11 '19 at 12:45
If you want to open bunch of files just to do 'search/occur', you can use the_silver_searcher (with helm-ag) to search things even for non visited files. — azzamsa, Jan 12 '19 at 08:41

score 2 · Accepted Answer · answered Jan 14 '19 at 00:07

I have come to the following solution. Similar to the answer proposed by James Anderson, but replacing the re-search-forward with thing-at-point, and a few other changes based on some other references.

  (defun open-a-bunch-of-files ()
    "Open a a bunch of files, given a text file containing a list of file names"
    (interactive)
    (setq my_filelist (completing-read "my_filelist: " nil nil nil))
    (with-temp-buffer
      (insert-file-contents my_filelist)
      (goto-char (point-min))
      (while (not (eobp))
        (find-file-noselect (replace-regexp-in-string "\n$" "" (thing-at-point 'line t)))
        (forward-line)
      )
    )
  )

References:

https://emacs.stackexchange.com/questions/19518/is-there-an-idiomatic-way-of-reading-each-line-in-a-buffer-to-process-it-line-by

Grab current line in buffer as a string in elisp

How do I delete the newline from a process output?

score 1 · Answer 2 · answered Jan 09 '19 at 20:16

This seems to work on my machine:

(defun open-a-bunch-of-files (filelist)
  (with-temp-buffer
    (insert-file-contents filelist)
    (goto-char (point-min))
    (let ((done nil))
      (while (not done)
        (if (re-search-forward "^\\([a-z_A-Z:\/.0-9]+\\)$" nil t nil)
            (find-file-noselect (match-string 1))
          (setf done t))))))

(open-a-bunch-of-files "./filelist.txt")

you might need to futz around with the regex though (tested on a unix file system). And its emacs, so there is probably a better way that someone will probably point out. The buffers loaded will not be set to current buffer on purpose.

The `let` form seems kind of silly, just have `re-search-forward` stop when it finds no more mataches. — tripleee, Jan 11 '19 at 13:04

How can I open a long list of files from within emacs

2 Answers2