In a Scheme buffer, if the user tries to evaluate an expression and no
Scheme process is running, Emacs signals an error.  This is not very
useful; Emacs can indeed do better.

With the following patch Emacs asks the user in such cases which
Scheme program to start, presenting `scheme-program-name' as the
default choice.

2005-06-12  Emilio C. Lopes  <eclig@gmx.net>

        * cmuscheme.el (switch-to-scheme, scheme-proc): call
        `scheme-interactively-start-process' if no Scheme buffer/process
        available.
        (scheme-get-process): new function extracted from `scheme-proc'
        (scheme-interactively-start-process): new function