+;; NOTE: MIT Cscheme, when invoked with the -emacs flag, has a special user
+;; interface that communicates process state back to the superior emacs by
+;; outputting special control sequences. The gnumacs package, xscheme.el, has
+;; lots and lots of special purpose code to read these control sequences, and
+;; so is very tightly integrated with the cscheme process. The cscheme
+;; interrupt handler and debugger read single character commands in cbreak
+;; mode; when this happens, xscheme.el switches to special keymaps that bind
+;; the single letter command keys to emacs functions that directly send the
+;; character to the scheme process. Cmuscheme mode does *not* provide this
+;; functionality. If you are a cscheme user, you may prefer to use the
+;; xscheme.el/cscheme -emacs interaction.
+;;
+;; Here's a summary of the pros and cons, as I see them.
+;; xscheme: Tightly integrated with inferior cscheme process! A few commands
+;; not in cmuscheme. But. Integration is a bit of a hack. Input
+;; history only keeps the immediately prior input. Bizarre
+;; keybindings.
+;;
+;; cmuscheme: Not tightly integrated with inferior cscheme process. But.
+;; Carefully integrated functionality with the entire suite of
+;; comint-derived CMU process modes. Keybindings reminiscent of
+;; Zwei and Hemlock. Good input history. A few commands not in
+;; xscheme.
+;;
+;; It's a tradeoff. Pay your money; take your choice. If you use a Scheme
+;; that isn't Cscheme, of course, there isn't a choice. Xscheme.el is *very*
+;; Cscheme-specific; you must use cmuscheme.el. Interested parties are
+;; invited to port xscheme functionality on top of comint mode...
+
+;;; CHANGE LOG
+;;; ===========================================================================
+;;; 8/88 Olin
+;;; Created.
+;;;
+;;; 2/15/89 Olin
+;;; Removed -emacs flag from process invocation. It's only useful for
+;;; cscheme, and makes cscheme assume it's running under xscheme.el,
+;;; which messes things up royally. A bug.
+;;;
+;;; 5/22/90 Olin
+;;; - Upgraded to use comint-send-string and comint-send-region.
+;;; - run-scheme now offers to let you edit the command line if
+;;; you invoke it with a prefix-arg. M-x scheme is redundant, and
+;;; has been removed.
+;;; - Explicit references to process "scheme" have been replaced with
+;;; (scheme-proc). This allows better handling of multiple process bufs.
+;;; - Added scheme-send-last-sexp, bound to C-x C-e. A gnu convention.
+;;; - Have not added process query facility a la cmulisp.el's lisp-show-arglist
+;;; and friends, but interested hackers might find a useful application
+;;; of this facility.