This directory, cmds/cc68, contains the source code for our 68000 C compiler,
  assembler, linker and random utilities, some of which even work.  There are
  versions which run on V and versions which run on (VAX) Unix.

The comments in this file assume that there are only two versions: (VAX) Unix
  and Sun V.  In fact, there are probably more V versions for MicroVAXen,
  Fireflies, etc.

NOTE: This is effectively the home of the 68000 C compiler used all over the
  Stanford campus, not just in the V system.  Be a little careful before
  installing the Unix versions (or the V-system versions, for that matter,
  since we can't get much work done without the compiler).

There are sources here for:
  as68	    Assembler
  ccom68    Guts of the C compiler
  c268	    Optimizer (Pessimizer?)
  cpp	    C preprocessor
  cc68	    Front end that invokes cpp, ccom68, c268, as68, ld68
  ld68	    Linker
  rev68	    Byte-swaps data to overcome vax/68000 byte-ordering differences (?)
* nm68	    Lists symbol table in object/executable file
* size68    Lists sizes of segments in executable file
* rl68	    Lists relocation commands in object file
* pr68	    Yet another command to extract information from object/exe files
* dl68	    Down-line loader for talking to 68000 development systems
* ranlib68  68000 equivalent of ranlib(1) [ broken? ]
* lorder68  Crock (shell script) which we use instead of ranlib68

* We only build a Unix version of these, for the not-very-good reason that
  no-one has invested the effort to port them to V.

It seemed like a good idea to keep these all in one place, rather than having
a separate directory in cmds for each one.  It also doesn't seem like a good
idea to pack these all in one directory, so...

The structure of this directory, and its buildfiles, is not quite as simple as
for most cmds directories.  The directory structure looks like

	cc68/
	    as/
		buildfile	    - Calls {m68k,unix}/buildfile, i.e.
				      builds all versions of as68
		mi/
		    buildfile	    - Does the same thing as ../buildfile
		    buildtemplate   - see immediately below...
		m68k/
		    buildfile	    - Includes /xV/cmds/m68k/buildtemplate and
				      ../mi/buildtemplate, i.e. builds
				      m68k (Sun V) version of as68
		unix/
		    buildfile	    - Includes /xV/cmds/unix/buildtemplate and
				      ../mi/buildtemplate, i.e. builds
				      unix (VAX Unix) version of as68
	    c2/			- Generates c268	     )
	    cc/			- Generates cc68 itself	     ) All these have
	    ccom/		- Generates ccom68	     ) same structure
	    cpp/		- Generates cpp		     ) as above.
	    ld/			- Generates ld68 and friends )

-->	    buildfile		- Master buildfile.  Calls 
				  {m68k,unix}/buildfile, i.e. builds all 
				  versions of everything.
	    buildtemplate	- Calls {as,c2,cc,ccom,cpp,ld}/(some machine
				  type)/buildfile.  See immediately below...
	    subdirs		- Defines "SUBDIRS = m68k unix".  Included
				  by {.,as,c2,cc,ccom,cpp,ld}/buildfile.
	    m68k/		- Generates m68k version of everything.
				  No binaries are put in here; it's just a
				  home for the buildfile.
		buildfile	    - Includes ../buildtemplate
	    unix/		- Generates Unix version of everything.
		buildfile	  Same structure as m68k.

and could, of course, be expanded to produce code for MicroVAX V, Firefly V,
etc.  All the source code currently lives in the mi directories, although we
use the VPATH mechanism so that private versions could also exist in machine-
specific directories.

Future Work: see NOTES file.
