[Orgmode] Re: Ignoring non-existent agenda files

[Clifford Caoile]

Hello emacs-orgmode mailing list:

I too would like the ability for org-mode to ignore (silently)
non-existent agenda files. This has been discussed before on the
mailing list [1].

Basically my use case is with Emacs on Windows. I have one Org Agenda
file on removable storage (USB memory), which I want to use from
multiple computers, so sometimes that file is not available. I tried
modifying the org-mode elisp files as shown below. When the
interactive prompt "non-existent file <filename>.. [R]emove from list
or [A]bort?" is shown, I press the "c" key to continue.

---gitk output---
[author/committer is me, but info is redacted]
Parent: 6f3026edf161ae2d721f4ac04ed50fdebb16353d (Release 6.35g)

    Continuing loading when agenda org files do not exist temporarily (press c)

--------------------------------- lisp/org.el ---------------------------------
index c89c5ac..89c5d88 100644
@@ -14896,6 +14896,8 @@ Optional argument FILE means use this file
instead of the current."
        ((equal r ?r)
        (org-remove-file file)
        (throw 'nextfile t))
+       ((equal r ?c)
+       (throw 'nextfile t))
        (t (error "Abort"))))))

 (defun org-get-agenda-file-buffer (file)
---gitk output end---

Unfortunately, the above doesn't work correctly. I have to press "c"
multiple times in order to "c"ontinue.

I think the workaround suggested by Carsten Dominik [1], which is to
delete non-existent files from the org-agenda-files variable once,
could work for me if I change it to check the existence of the files
every time. Do you think this can be implemented as an elisp defadvice
on org-agenda<f>? Or is there some better way?

References:
[1] http://thread.gmane.org/gmane.emacs.orgmode/17408

Best regards and TIA,
Clifford Caoile