The EDWIN option.

This option extends Scheme with a source code (text) editor.  It is
built in the GNU standard way:

    ./configure ...
    make all
    make check
    make install

The last command will attempt to create a subdirectory in the first
directory on Scheme's library path.  If that directory is not writable
by you, super-user privileges may be required.

You can put a writable directory at the front of your Scheme's library
path by setting the MITSCHEME_LIBRARY_PATH environment variable and
creating a short optiondb file.

    mkdir ~/.mit-scheme-x86-64
    echo "(further-load-options #t)" > ~/.mit-scheme-x86-64/optiondb.scm
    export MITSCHEME_LIBRARY_PATH=\
	~/.mit-scheme-x86-64:/usr/local/lib/mit-scheme-x86-64
    make install

To use: call the global `edit' procedure, or specify --edit on the
Scheme command line.  For more information see the MIT/GNU Scheme
User's Manual.

Notes on the Edwin sources:

If you want to add a new file to the source tree, you need to 
modify the following three files:

	decls.scm
	ed-ffi.scm
	edwin.pkg

If the file should be loaded into the default edwin band, you must also
edit the file:

	edwin.ldr

If the file is to be autoloaded, you must edit the file:

	loadef.scm

So, in either case, you have to change four files.