Can we make ff-find-other-file to search recursively in directories which are listed in ff-search-directories.
Instead of searching only in /usr/include, it would also search in /usr/include/llvm. Or likewise.
I've added this function to my .emacs file:
(defun get-all-subdirectories(dir-list)
"Returns a list of all recursive subdirectories of dir-list,
ignoring directories with names that start with . (dot)"
(split-string
(shell-command-to-string
(concat "find "
(mapconcat 'identity dir-list " ")
" -type d -not -regex \".*/\\\..*\""))))
And, in my c-mode-common-hook, I have this:
(setq ff-search-directories (get-all-subdirectories (list "dirA" "dirB")))
This assumes you have a standard Unix find command in your PATH. If you're on Windows, you can get a copy of find here: http://unxutils.sourceforge.net/
It takes a little while to run if you have many directories for it to recurse through.
Add a /* after the directories where you want subdirectories searched. So set ff-search-directories so that it contains "/usr/include/*".
来源：https://stackoverflow.com/questions/15983493/emacs-ff-find-other-file-and-ff-search-directories-isnt-recursive