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C00002 00002	∂23-FEB-76  1503	FTP: host HARV 
C00006 00003		FORREST W. HOWARD JR.
C00007 00004	∂09-MAR-76  1311	FTP:HOWARD at HARV-10	LISP/BOOK    
C00010 00005	
C00016 00006	∂24-MAY-76  1141	FTP: host HARV 
C00020 ENDMK
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∂23-FEB-76  1503	FTP: host HARV 
***** FTP mail from [7101,422] (HOWARD)
JOHN:
	I FINISHED TRANSFERING THE FILES. YOU WILL FIND (I HOPE) THE
FOLLOWING ON YOUR DIRECTORIES:

   BUILDL.DOC LMAN.DOC EDIT1.DOC EDIT2.DOC MI.DOC GUTS.DOC

	AUXFNS SVLISP HACK TRACE EDIT BT 

    SPARM.M11 LGLOB.M11 MACRO.M11 DSTUF.M11  ATDAT.M11
     E     SUBR.M11 SUBRCOM.M11 EARLY.M11 SYSS.M11 GCOL.M11 NOW.M11 FP.M11
     SYSEND.M11 PROB7.M11 PROB8.M11 PROB8.ORI PRO
     CTABLE.M11 PROBEND FILLER.M11 NOROOM.M11 

		MI.TEC

		SHRLISP

  THE USER'S MANUAL IS LMAN.DOC... BUILDLISP.DOC TELLS HOW TO MAKE A LISP
FROM SCRATCH. GUTS.DOC DESCRIBS THE INTERNALS OF THE LISP SYSTEM.
THE EDIT FILES ARE FOR THE IN-CORE EDITOR THAT NO-ONE
USES SINCE WE'VE PUT IN (TECO 'FILE) AND (TECF(FUNC1 ... FUCN)).

THE SECOND GROUP IS THE LIBRARY.  AUXFNS IS PRE-LOADED, WITH HACK AND SVLISP. THE OTHER'S ARE LOADED BY THE USER WHEN HE WISHES.

THE THIRD GROUP IS THE SOURCE FOR LISP. THE FILE MI.TEC IS A OFTEN USED
MACRO FOR LIST STRUCTURE INSERTION . THE FILE SHRLISP IS TEHE UNIX
CCL FILE TO MAKE A LISP.

I HOPE THAT THIS IS WHAT YOU NEED.  IF THERE IS ANY OTHER PART
OF UNIX LISP THAT YOU WANT TO GET AHOLD OF, LET ME KNOW.

			FORREST HOWARD

(PS PLEASE LET ME KNOW IF YOU GIVE A COPY OF LISP TO ANYONE ELSE.
 YOU'RE WELCOME TO DO SO, BUT I'D LIKE TO KEEP TRACK OF WHERE
 IT LIVES.)

	FORREST W. HOWARD JR.
	CENTER FOR RESEARCH IN COMPUTING TECHNOLOGY
	AIKEN COMPUTATION LAB
	HARVARD UNIVERSIT
	CAMBRIDGE, MA. 02138

		GOOD LUCK

			FORREST

∂09-MAR-76  1311	FTP:HOWARD at HARV-10	LISP/BOOK    
Date:  9 Mar 1976 1610-Edt
From: HOWARD at HARV-10
Subject: LISP/BOOK
To:   JRA  at SU-AI

JOHN:

SORRY I TOOK SO LONG TO GET BACK TO YOU. FIRST YOUR COMMENTS:

	THE FRMPTR WAS A CELL I ADDED AT THE REQUEST OF AN UNDERGRAD
	(JOHN BURRUS)  THAT HE FELT NECESSARY TO  IMPLEMENT SPAGETTI
	STACKS.  HOWEVER, THAT WAS LAST SPRING, AND JOHN HAS GONE FORTH
	TO MAJOR IN ENGLISH.  SPAGETTI STACKS ARE SOMETHING I'M PLANNING
	EVENTUALLY (MAYBE LATE SUMMER).

	XFER LISP IS THE PDP-10- UNIX  ENVIRONMENT TRANSFER PROJECT, WHICH
	I'M DOING TO JUSTIFY MY EXISTANCE THESE DAYS. WE'RE PLANNING
	ON TRANSFERING A COMPLETE ENVIRONMENT (DATA AND CONTROL) TO THE
		10 TO CONTINUE RUNNING WHEN WE'RE BLOCKED ON THE 1.( AT 
	THE MOMENT "BLOCKED" MEANS NO CORE, BUT WE EVENTUALLY HOPE TO DEVISE
	ALGORITHIMS FOR THE MONITOR TO "TELL" LISP IT'S BLOCKED).

	THE OBLIST SWITCHING IS SOMETHING I DID LAST SPRING WHEN TAKING
	A COURSE AT MIT UNDER RON RIVEST. SEE THE CURRENT ACM FOR  THE 
	SPECIFICS.. BASICALLY, IT A "MOVE TOWARDS THE FRONT" ALGORITHIM

	TO  SPEED UP OBLIST SEARCHING.

INDEED THIS IS CLOSE TO PRENNER'S LISP-- WHEN I ORIGINALLY WROTE AS AN UUNDERGRAD,
WE WE CONVERTING APPL. MATH [[0 (MACHINE LANGUAGE) TO UNIX FROM A 10, AND
WERE TRYING TO MAKE THE COURSES (AND PROBLEM SETS AND LISP)
AS IDENTICAL AS POSSIBLE.

I WILL BE INTERESTED IN SEEING THE BOOK... SOUNDS LIKE IT SHOULD BE GOOD
READING

TQAKE CARE
				FORREST


I SHOULD MENTION THAT OTHER GOODIES ARE AVAILABLE FROM THE SAME
ADDRESS, INCLUDING TECO, RT-11 BASIC,  A DDT, SOURCES FOR THE
ASSEMBLER AND LINKER, AND A PROGRAMMING LANGUAGE CALLED "PPL",
STANDING FOR POLYMORPHIC PROGRAMMING LANGUAGE.  THESE ARE ALL ON
A BASIS SIMILAR TO LISP.  ECL FOR THE 11 IS ALSO COMMING SOON.

OTHER GOODIEES ARE AVAILABLE FROM BERKELY (INGRESS, A DATA BASE
SYSTEM), COMMERCIAL UNION LEASING CO, NEW YORK (FORTRAN 4-PLUS ) (YECH!!)
AND THE NAVAL POST-GRADUATE SCHOOL (A DEBUGER AND OTHER STUFF). BELL IS
RUMORED TO BE WORKING ON ALGOL-68 COMPILERS.
3) YOUR BOOK WAS READ FOR THE SECOND TIME LAST SATURDAY.   TYPO'S
I NOTICED WERE "ABRECIATION" FOR ABREVIATION (ABOUT PAGE 30)
(YOU MIGHT HAVE MEANT THIS) AND SEVERAL PLACES TOWARDS THE
BACK OF THE BOOK WHERE THE PABE NUMBERING WAS SCREWED UP
IN ITS TYPEOUT.

I RESPECT TO FORMAT, I FOUND THE BOOK FAIRLY INTERESTING.
THE SECTIONS THAT I MOST WANTED TO SEE (FUNARGS, SPAGETTI,
QUANATATIVE TRADEOFFS BETWEEN SM AND DEEP-BINDING) WERE ALL
"MORE ON ...." SECTIONS. THE REST OF IT SEEMS WELL THOUGHT OUT,
AND WELL PRESENTED.
I'M NOT SURE IF I AGREE WITH THE ADVOIDANCE OF NIL AND T,
AS WELL AS THE CONCEPT OF FIRST, SECOND, ...; IT SEEMS TO ME
THAT JUST AS THE PROGRAMMER IN ASSEMBLER KNOWS THAT A 0 IS
FALSE OR HALT, AND A 1 IS TRUE OR AN INSTRUCTION, THE LISP
USER SHOULD BE AWARE OF THE
DUALITY OF VARIOUS OBJECTS.  THE NOTION OF FIRST&CO. WOULD SEEM
TO HELP CONFUSE THE HOPEFULLY CLEAR RELATIONSHIP BETWEEN LISTS
AND DOTTED-PAIRS.

THE OVERALL ORGINIZATION IS GOOD.  THE IDEA OF PRESENTING LISP
MATHEMATICALLY FIRST, FOLLOWED BY THE ISSUES AND THEN A COMPILE
TO SEE HOW TO DO THINGS SEEMS REASONABLE.

	I PROMISE TO READ A THIRD TIME, AND MAKE FULL COMENTS THEN.


	ONE MORE THING, I'M LEAVING FOR PARIS ON JUNE 1, SO TRY
TO GET CORROSPENDENCE TO ME BY THEN. I PLAN TO LOG IN HERE ABOUT
ONCE EVERY 2 WEEKS (FROM THE LONDON TIP), SO POST THAT MAIL AND
YOU'LL EVENTUALLY GET AN ANSWER.  AFTER OCTOBER I'LL BE WORKING FOR
COMMERCIAL UNION LEASING CO, 645 MADISON, NYC, 10022 (I THINK)
SO SNAIL-MAIL CAN GET ME THERE (I HOPE TO ALSO KEEP THIS ACCOUNT).

				FORREST

∂24-MAY-76  1141	FTP: host HARV 
***** FTP mail from [7101,422] (HOWARD)
JOHN:
 A QUICK REPLY TO YOUR LETTER:

 1) UNIX RUNS ON ANY 11 WITH SEGMENTATION (MEMORY MANAGEMANT UNIT) AND
EXTENDED INSTRUCTION SET (IF A 11/40 (THIS MEANS SOB, MUL, DIV)).
ONE BLOCK TYPE DEVICE IS REQUIRED (DECTAPE, RK DISK, RP DISK, ETC).
IT IS EXTREMLY FLEXIBLE IN THE CONFIGURATIONS THAT IT ACCEPTS; I
HAVE RUN UNICIES WITH ONE DECTAPE AS A "ROOT FILESYSTEM" AND SWAP
DEVICE, AND THE OTHER DECTAPE AS A "REMOVABLE FILESYSTEM".
THE BIGGER AND FASTER THE DISKS/TAPES THE BETTER, BUT ALMOST ANYTHING
WILL DO.
   UNIX SUPPORTS ALMOST ANY PERHIPERAL MADE BY DEC, AND QUITE AFEW FOREIGN
PERHIPERALS (VOICE SYNTHESISERS, PHOTOTYPESETTERS, GOULD PRINTERS, ETC.).
  OH YES -- YOU NEED MEMORY TO MANAGE.  ABOUT 64 K WDS IS THE MINIMUM THAT I
WOULD CONSIDER, ALTHOUGH I'VE SEEN SMALLER.
  2) RUMOR HAS IT THAT BELL HAS UNICIES TO RUN ON THE LSI-11 AND 11/20 OR
11/05. YOU'LL HAVE TO TALK TO THEM TO FIND OUT.
  3) UNIX MAY BE CONVERABLE TO A DEC MONITOR.  THE WAY DEC ORGANIZES THEIR
STACK-PROT
STACK/PROGRAM/DATA IS DIFFERENT THAN UNIX (DEC LIKES PROG HIGH IN CORE, 
DATA IMMEDIATLY BELOW, STACK BELOW THAT. UNIX LIKES PROG LOW, DATA FOLLOWING AND
STACK STARTING AT -2 GROWING TOWARDS 0.) MAPING THE SYSTEM CALLS WILL BE FAIRLY
ESASY, AS I'VE TRIED TO (AT LEAST INITIALLY) TO LEAVE ALL THE
SYSTEM DEPENDENT STUFF IN ONE MODULE (THIS EFFORT HAS DETERIORATED OVER TIME).
AS A LAST RESORT, AL SPECTOR AT HARVARD WROTE A UNIX "MONITOR" THAT FITS
INTO A BARE MACHINE AND CAN BE USED TO HELP  OUT WITH STUFF. AL WILL BE A
1-G AND STANFORD NEXT YEAR.
  4) THE BIGGEST LOSS ABOUT USING UNIX LISP UNDER A DEC MONITOR OR 11-40 IS THE
LOSS OF I&D SPACE SEPERATION CAPABILITY.  UNDER AN 11-45 OR EQUIVILANT, THE
USER HAS ABOUT 27.5 K OF DATA (NOT COUNING STACK) TO DO THINGS WITH.
THIS DROPS TO ABOUT 22K UNDER AN 11/40 OR NON-I&D MACHINE.
(P.S. ANOTHER ADVANTAGE OF I&D IS THE "FREENESS" OF NEW SUBRS  OR FSUBRS.
THAT IS THE CODE FOR NEW SUBRS JUST POPS INTO I-SPACE, AND DSPACE REMAINS THE 
SAME SIZE, WITH THE LANGUAGE BEING MORE POWERFUL AND/OR CONVENIENT.)

  MORE ON THE BOOK TO COME.  I GOTTA CODE RIGHT NOW, HOWEVER (I HEAR THAT
PLANE DRAWING CLOSE).

			FORREST