Add file to org-agenda-files from another agenda file?

Question

I have one file that is my default file in org-agenda-files (which I set in my init.el file).

How can I add other files to the org-agenda-files list from within my default agenda file with paths relative to the default file?

Hypothetical example:

* One heading
  Some text
* Second heading (external)
  AGENDAFILE: ext/ext.org

Answer 1

You can use a file-local variable to evaluate a lisp form that will add another file to your org-agenda-files list.

For example, you could put the following at the end of your default agenda file to add the another-agenda-file.org file to the list.

## Local Variables:
## eval: (add-to-list 'org-agenda-files "another-agenda-file.org" 'append)
## End:

The append argument (or any non-nil value) in the call to add-to-list puts the file at the back of the list. Leaving it off will put the file at the front of the list.

Answer 2

Another easy way is to set the org-agenda-files variable to a directory instead of a file. Thus, any file in the directory will be tracked.

I have not tested it yet but I am pretty sure that it also works with symlinks, so this would work in almost any scenario.

see this answer on SO.