### 3.15 Emacs

`C-h C-i` (`info-lookup-symbol`) is a good way to find documentation on C functions while editing (see Info Documentation Lookup in The Emacs Editor).

The GMP manual can be included in such lookups by putting the following in your `.emacs`,

    (eval-after-load "info-look"
      '(let ((mode-value (assoc 'c-mode (assoc 'symbol info-lookup-alist))))
         (setcar (nthcdr 3 mode-value)
                 (cons '("(gmp)Function Index" nil "^ -.* " "\\>")
                       (nth 3 mode-value)))))