>Another question:  Is it possible to build the system completely from 
>scratch, without using a preexisting image file (but with a changes file
>and the sources)?  If I take the C sources and build the VM, can I have it
>build the system from the sources?  How? -- where's that documented?

Joe,

I think you are asking for a way of completely re-constructing
an image from source files. There is currently no way to do this;
we have always worked by mutating an existing image. Even the original
Squeak image was mutated from the Apple Smalltalk image, which
was mutated from the Xerox Smalltalk-80 image, which, for all
I know, goes all the way back to some Smalltalk-76 image at
Xerox PARC.

Other Smalltalk's have ways of bootstrapping an image from
source files (Gnu Smalltalk and Little Smalltalk, for example),
but it we've never had to do that in our evolutionary
path. Note that you can easily file out the source code for all
the classes in the system as a record of what's there.

I suspect it would not be too difficult to write a program
(in Squeak) that parsed these files and built up a new
image (in a separate memory area, like the VM simulator does).
You'd have to add some additional code
to initialize the System Dictionary, initialize the process
scheduler, create an initial process, initialize the array
of objects that must be known to the VM, and a few other
such chores. You could look at the System Tracer for
guidance with this. The resulting program would serve as
a form of documentation for system hackers.

	-- John