How do I get a list of Emacs lisp non-interactive functions?

Question

How do I get a complete list of non-interactive functions that I can use in Emacs Lisp?

The interactive ones are easy enough to find in the help system, but I want a complete list of all the other functions I can use. For example concat, car, cdr, etc. (And preferably with documentation).

Thanks

Ed

Edit: Answered thanks to Jouni. I played around with his answer a bit, and got it to sort the results (using the results of his code to help me find the correct sorting function!)

(flet ((first-line (text)
                   (if text
                       (substring text 0 (string-match "\n" text))
                     "")))
  (let ((funclist (list)))
    (mapatoms 
     (lambda (x)
       (and (fboundp x)                     ; does x name a function?
            (not (commandp (symbol-function x))) ; is it non-interactive?
            (subrp (symbol-function x))          ; is it built-in?
            (add-to-list 'funclist 
                         (concat (symbol-name x) " - " (first-line (documentation x))
                                 "\n")))))
    (dolist (item (sort funclist 'string<))
      (insert item))))

Answer 1

Here's the basic idea - see the Emacs Lisp manual for any unclear concepts.

(flet ((first-line (text)
         (if text
             (substring text 0 (string-match "\n" text))
           "")))
  (mapatoms 
   (lambda (x)
     (and (fboundp x)                          ; does x name a function?
          (not (commandp (symbol-function x))) ; is it non-interactive?
          (subrp (symbol-function x))          ; is it built-in?
          (insert (symbol-name x) " - " (first-line (documentation x)) "\n")))))