March 24, 1983
Real Programmers Don't Use PASCAL
Ed Post
Tektronix, Inc.
P.O. Box 1000 m/s 63-205
Wilsonville, OR 97070
Copyright (c) 1982
(decvax | ucbvax | cbosg | pur-ee | lbl-unix)!teklabs!iddic!evp
Back in the good old days -- the "Golden Era" of computers, it was
easy to separate the men from the boys (some times called "Real Men" and
"Quiche Eaters" in the literature). During this period, the Real Men
were the ones that understood computer programming, and the Quiche Eaters
were the ones that didn't. A real computer programmer said things like "DO
10 I=1,10" and "ABEND" (they actually talked in capital letters, you
understand), and the rest of the world said things like "computers are too
complicated for me" and "I can't relate to computers -- they're so
impersonal". (A previous work [1] points out that Real Men don't "relate"
to anything, and aren't afraid of being impersonal.)
But, as usual, times change. We are faced today with a world in which
little old ladies can get computers in their microwave ovens, 12 year old
kids can blow Real Men out of the water playing Asteroids and Pac-Man, and
anyone can buy and even understand their very own Personal Computer. The
Real Programmer is in danger of becoming extinct, of being replaced by
high-school students with TRASH-80s.
There is a clear need to point out the differences between the
typical high-school junior Pac-Man player and a Real Programmer. If this
difference is made clear, it will give these kids something to aspire to a
role model, a Father Figure. It will also help explain to the employers of
Real Programmers why it would be a mistake to replace the Real Programmers
on their staff with 12 year old Pac-Man players (at a considerable salary
savings).
LANGUAGES
---------
The easiest way to tell a Real Programmer from the crowd is by the
programming language he (or she) uses. Real Programmers use FORTRAN.
Quiche Eaters use PASCAL. Nicklaus Wirth, the designer of PASCAL, gave a
talk once at which he was asked "How do you pronounce your name?". He
replied, "You can either call me by name, pronouncing it 'Veert', or call
me by value, 'Worth'." One can tell immediately from this comment that
Nicklaus Wirth is a Quiche Eater. The only parameter passing mechanism
endorsed by Real Programmers is call-by-value-return, as implemented in
the IBM/370 FORTRAN G and H compilers. Real programmers don't need all
these abstract concepts to get their jobs done -- they are perfectly happy
with a keypunch, a FORTRAN IV compiler, and a beer.
* Real Programmers do List Processing in FORTRAN.
* Real Programmers do String Manipulation in FORTRAN.
* Real Programmers do Accounting (if they do it at all) in FORTRAN.
* Real Programmers do Artificial Intelligence programs in FORTRAN.
If you can't do it in FORTRAN, do it in assembly language. If you can't
do it in assembly language, it isn't worth doing.
STRUCTURED PROGRAMMING
---------- -----------
The academics in computer science have gotten into the "structured
programming" rut over the past several years. They claim that programs
are more easily understood if the programmer uses some special language
constructs and techniques. They don't all agree on exactly which
constructs, of course, and the examples they use to show their particular
point of view invariably fit on a single page of some obscure journal or
another -- clearly not enough of an example to convince anyone. When I got
out of school, I thought I was the best programmer in the world. I could
write an unbeatable tic-tac-toe program, use five different computer
languages, and create 1000 line programs that WORKED. (Really!) Then I
got out into the Real World. My first task in the Real World was to read
and understand a 200,000 line FORTRAN program, then speed it up by a
factor of two. Any Real Programmer will tell you that all the Structured
Coding in the world won't help you solve a problem like that -- it takes
actual talent. Some quick observations on Real Programmers and Structured
Programming:
* Real Programmers aren't afraid to use GOTOs.
* Real Programmers can write five page long DO loops without getting
confused.
* Real Programmers like Arithmetic IF statements -- they
make the code more interesting.
* Real Programmers write self-modifying code, especially if they can save
20 nanoseconds in the middle of a tight loop.
* Real Programmers don't need comments -- the code is obvious.
* Since FORTRAN doesn't have a structured IF, REPEAT ... UNTIL, or CASE
statement, Real Programmers don't have to worry about not using them.
Besides, they can be simulated when necessary using assigned GOTOs.
Data structures have also gotten a lot of press lately. Abstract
Data Types, Structures, Pointers, Lists, and Strings have become popular
in certain circles. Wirth (the above-mentioned Quiche Eater) actually
wrote an entire book [2] contending that you could write a program based
on data structures, instead of the other way around. As all Real
Programmers know, the only useful data structure is the Array. Strings,
Lists, Structures, Sets -- these are all special cases of arrays and can
be treated that way just as easily without messing up your programing
language with all sorts of complications. The worst thing about fancy data
types is that you have to declare them, and Real Programming Languages, as
we all know, have implicit typing based on the first letter of the (six
character) variable name.
OPERATING SYSTEMS
--------- -------
What kind of operating system is used by a Real Programmer? CP/M?
God forbid -- CP/M, after all, is basically a toy operating system. Even
little old ladies and grade school students can understand and use CP/M.
Unix is a lot more complicated of course -- the typical Unix hacker
never can remember what the PRINT command is called this week -- but when
it gets right down to it, Unix is a glorified video game. People don't do
Serious Work on Unix systems: they send jokes around the world on UUCP-net
and write adventure games and research papers.
No, your Real Programmer uses OS/370. A good programmer can find and
understand the description of the IJK305I error he just got in his JCL
manual. A great programmer can write JCL without referring to the manual
at all. A truly outstanding programmer can find bugs buried in a 6
megabyte core dump without using a hex calculator. (I have actually seen
this done.)
OS is a truly remarkable operating system. It's possible to destroy
days of work with a single misplaced space, so alertness in the
programming staff is encouraged. The best way to approach the system is
through a keypunch. Some people claim there is a Time Sharing system that
runs on OS/370, but after careful study I have come to the conclusion that
they were mistaken.
PROGRAMMING TOOLS
----------- -----
What kind of tools does a Real Programmer use? In theory, a Real
Programmer could run his programs by keying them into the front panel of
the computer. Back in the days when computers had front panels, this was
actually done occasionally. Your typical Real Programmer knew the entire
bootstrap loader by memory in hex, and toggled it in whenever it got
destroyed by his program. (Back then, memory was memory -- it didn't go
away when the power went off. Today, memory either forgets things when you
don't want it to, or remembers things long after they're better
forgotten.) Legend has it that Seymour Cray, inventor of the Cray I
supercomputer and most of Control Data's computers, actually toggled the
first operating system for the CDC7600 in on the front panel from memory
when it was first powered on. Seymour, needless to say, is a Real
Programmer.
One of my favorite Real Programmers was a systems programmer for
Texas Instruments. One day, he got a long distance call from a user whose
system had crashed in the middle of saving some important work. Jim was
able to repair the damage over the phone, getting the user to toggle in
disk I/O instructions at the front panel, repairing system tables in hex,
reading register contents back over the phone. The moral of this story:
while a Real Programmer usually includes a keypunch and lineprinter in his
toolkit, he can get along with just a front panel and a telephone in
emergencies.
In some companies, text editing no longer consists of ten engineers
standing in line to use an 029 keypunch. In fact, the building I work in
doesn't contain a single keypunch. The Real Programmer in this situation
has to do his work with a "text editor" program. Most systems supply
several text editors to select from, and the Real Programmer must be
careful to pick one that reflects his personal style. Many people believe
that the best text editors in the world were written at Xerox Palo Alto
Research Center for use on their Alto and Dorado computers [3].
Unfortunately, no Real Programmer would ever use a computer whose
operating system is called SmallTalk, and would certainly not talk to the
computer with a mouse.
Some of the concepts in these Xerox editors have been incorporated
into editors running on more reasonably named operating systems -- EMACS
and VI being two. The problem with these editors is that Real Programmers
consider "what you see is what you get" to be just as bad a concept in
Text Editors as it is in Women. No, the Real Programmer wants a "you asked
for it, you got it" text editor -- complicated, cryptic, powerful,
unforgiving, dangerous. TECO, to be precise.
It has been observed that a TECO command sequence more closely
resembles transmission line noise than readable text [4]. One of the more
entertaining games to play with TECO is to type your name in as a command
line and try to guess what it does. Just about any possible typing error
while talking with TECO will probably destroy your program, or even worse
-- introduce subtle and mysterious bugs in a once working subroutine.
For this reason, Real Programmers are reluctant to actually edit a
program that is close to working. They find it much easier to just patch
the binary object code directly, using a wonderful program called SUPERZAP
(or its equivalent on non-IBM machines). This works so well that many
working programs on IBM systems bear no relation to the original FORTRAN
code. In many cases, the original source code is no longer available. When
it comes time to fix a program like this, no manager would even think of
sending anything less than a Real Programmer to do the job -- no Quiche
Eating structured programmer would even know where to start. This is
called "job security". Some programming tools NOT used by Real
Programmers:
* FORTRAN preprocessors like MORTRAN and RATFOR. The Cuisinarts of
programming -- great for making Quiche. See comments above on structured
programming.
* Source language debuggers. Real Programmers can read core dumps.
* Compilers with array bounds checking. They stifle creativity, destroy
most of the interesting uses for EQUIVALENCE, and make it impossible to
modify the operating system code with negative subscripts. Worst of all,
bounds checking is inefficient.
* Source code maintainance systems. A Real Programmer keeps his code locked
up in a card file, because it implies that its owner cannot leave his
important programs unguarded [5].
THE REAL PROGRAMMER AT WORK
--- ---- ---------- -- ----
Where does the typical Real Programmer work? What kind of programs
are worthy of the efforts of so talented an individual? You can be sure
that no real Programmer would be caught dead writing accounts-receivable
programs in COBOL, or sorting mailing lists for People magazine. A Real
Programmer wants tasks of earth-shaking importance (literally!).
* Real Programmers work for Los Alamos National Laboratory, writing atomic
bomb simulations to run on Cray I supercomputers.
* Real Programmers work for the National Security Agency, decoding Russian
transmissions.
* It was largely due to the efforts of thousands of Real Programmers working
for NASA that our boys got to the moon and back before the Russkies.
* The computers in the Space Shuttle were programmed by Real Programmers.
* Real Programmers are at work for Boeing designing the operating systems
for cruise missiles.
Some of the most awesome Real Programmers of all work at the Jet
Propulsion Laboratory in California. Many of them know the entire
operating system of the Pioneer and Voyager spacecraft by heart. With a
combination of large ground based FORTRAN programs and small
spacecraft-based assembly language programs, they are able to do
incredible feats of navigation and improvisation -- hitting ten-kilometer
wide windows at Saturn after six years in space, repairing or bypassing
damaged sensor platforms, radios, and batteries. Allegedly, one Real
Programmer managed to tuck a pattern matching program into a few hundred
bytes of unused memory in a Voyager spacecraft that searched for, located,
and photographed a new moon of Jupiter.
The current plan for the Galileo spacecraft is to use a gravity
assist trajectory past Mars on the way to Jupiter. This trajectory passes
within 80 +/- 3 kilometers of the surface of Mars. Nobody is going to
trust a PASCAL program (or PASCAL programmer) for navigation to these
tolerances.
As you can tell, many of the world's Real Programmers work for the
U.S. Government -- mainly the Defense Department. This is as it should
be. Recently, however, a black cloud has formed on the Real Programmer
horizon. It seems that some highly placed Quiche Eaters at the Defense
Department decided that all Defense programs should be written in some
grand unified language called "ADA" ((r), DoD). For a while, it seemed
that ADA was destined to become a language that went against all the
precepts of Real Programming -- a language with structure, a language with
data types, strong typing, and semicolons. In short, a language designed
to cripple the creativity of the typical Real Programmer. Fortunately,
the language adopted by DoD has enough interesting features to make it
approachable -- it's incredibly complex, includes methods for messing with
the operating system and rearranging memory, and Edsgar Dijkstra doesn't
like it [6]. (Dijkstra, as I'm sure you know, was the author of "GoTos
Considered Harmful" -- a landmark work in programming methodology,
applauded by Pascal Programmers and Quiche Eaters alike.) Besides, the
determined Real Programmer can write FORTRAN programs in any language.
The real programmer might compromise his principles and work on
something slightly more trivial than the destruction of life as we know
it, providing there's enough money in it. There are several Real
Programmers building video games at Atari, for example. (But not playing
them -- a Real Programmer knows how to beat the machine every time: no
challange in that.) Everyone working at LucasFilm is a Real Programmer.
(It would be crazy to turn down the money of fifty million Star Trek
fans.) The proportion of Real Programmers in Computer Graphics is somewhat
lower than the norm, mostly because nobody has found a use for Computer
Graphics yet. On the other hand, all Computer Graphics is done in FORTRAN,
so there are a fair number people doing Graphics in order to avoid having
to write COBOL programs.
THE REAL PROGRAMMER AT PLAY
--- ---- ---------- -- ----
Generally, the Real Programmer plays the same way he works -- with
computers. He is constantly amazed that his employer actually pays him to
do what he would be doing for fun anyway (although he is careful not to
express this opinion out loud). Occasionally, the Real Programmer does
step out of the office for a breath of fresh air and a beer or two. Some
tips on recognizing real programmers away from the computer room:
* At a party, the Real Programmers are the ones in the corner talking about
operating system security and how to get around it.
* At a football game, the Real Programmer is the one comparing the plays
against his simulations printed on 11 by 14 fanfold paper.
* At the beach, the Real Programmer is the one drawing flowcharts in the
sand.
* At a funeral, the Real Programmer is the one saying "Poor George. And he
almost had the sort routine working before the coronary."
* In a grocery store, the Real Programmer is the one who insists on running
the cans past the laser checkout scanner himself, because he never could
trust keypunch operators to get it right the first time.
THE REAL PROGRAMMER'S NATURAL HABITAT
--- ---- ------------ ------- -------
What sort of environment does the Real Programmer function best in?
This is an important question for the managers of Real Programmers.
Considering the amount of money it costs to keep one on the staff, it's
best to put him (or her) in an environment where he can get his work done.
The typical Real Programmer lives in front of a computer terminal.
Surrounding this terminal are:
* Listings of all programs the Real Programmer has ever worked on, piled in
roughly chronological order on every flat surface in the office.
* Some half-dozen or so partly filled cups of cold coffee. Occasionally,
there will be cigarette butts floating in the coffee. In some cases, the
cups will contain Orange Crush.
* Unless he is very good, there will be copies of the OSJCL manual and the
Principles of Operation open to some particularly interesting pages.
* Taped to the wall is a line-printer Snoopy calender for the year 1969.
* Strewn about the floor are several wrappers for peanut butter filled
cheese bars -- the type that are made pre-stale at the bakery so they
can't get any worse while waiting in the vending machine.
* Hiding in the top left-hand drawer of the desk is a stash of double-stuff
Oreos for special occasions.
* Underneath the Oreos is a flow-charting template, left there by the
previous occupant of the office. (Real Programmers write programs, not
documentation. Leave that to the maintainence people.)
The Real Programmer is capable of working 30, 40, even 50 hours at a
stretch, under intense pressure. In fact, he prefers it that way. Bad
response time doesn't bother the Real Programmer -- it gives him a chance
to catch a little sleep between compiles. If there is not enough schedule
pressure on the Real Programmer, he tends to make things more challenging
by working on some small but interesting part of the problem for the first
nine weeks, then finishing the rest in the last week, in two or three
50-hour marathons. This not only inpresses the hell out of his manager,
who was despairing of ever getting the project done on time, but creates a
convenient excuse for not doing the documentation. In general:
* No Real Programmer works 9 to 5 (Unless it's the ones at night.)
* Real Programmers don't wear neckties.
* Real Programmers don't wear high heeled shoes.
* Real Programmers arrive at work in time for lunch.
* A Real Programmer might or might not know his wife's name. He does,
however, know the entire ASCII (or EBCDIC) code table.
* Real Programmers don't know how to cook. Grocery stores aren't open at
three in the morning. Real Programmers survive on Twinkies and coffee.
THE FUTURE
--- ------
What of the future? It is a matter of some concern to Real
Programmers that the latest generation of computer programmers are not
being brought up with the same outlook on life as their elders. Many of
them have never seen a computer with a front panel. Hardly anyone
graduating from school these days can do hex arithmetic without a
calculator. College graduates these days are soft -- protected from the
realities of programming by source level debuggers, text editors that
count parentheses, and "user friendly" operating systems. Worst of all,
some of these alleged "computer scientists" manage to get degrees without
ever learning FORTRAN! Are we destined to become an industry of Unix
hackers and Pascal programmers?
From my experience, I can only report that the future is bright for
Real Programmers everywhere. Neither OS/370 nor FORTRAN show any signs of
dying out, despite all the efforts of Pascal programmers the world over.
Even more subtle tricks, like adding structured coding constructs to
FORTRAN have failed. Oh sure, some computer vendors have come out with
FORTRAN 77 compilers, but every one of them has a way of converting itself
back into a FORTRAN 66 compiler at the drop of an option card -- to
compile DO loops like God meant them to be.
Even Unix might not be as bad on Real Programmers as it once was.
The latest release of Unix has the potential of an operating system worthy
of any Real Programmer -- two different and subtly incompatible user
interfaces, an arcane and complicated teletype driver, virtual memory. If
you ignore the fact that it's "structured", even 'C' programming can be
appreciated by the Real Programmer: after all, there's no type checking,
variable names are seven (ten? eight?) characters long, and the added
bonus of the Pointer data type is thrown in -- like having the best parts
of FORTRAN and assembly language in one place. (Not to mention some of
the more creative uses for #define.)
No, the future isn't all that bad. Why, in the past few years, the
popular press has even commented on the bright new crop of computer nerds
and hackers ([7] and [8]) leaving places like Stanford and M.I.T. for the
Real World. From all evidence, the spirit of Real Programming lives on in
these young men and women. As long as there are illdefined goals, bizarre
bugs, and unrealistic schedules, there will be Real Programmers willing to
jump in and Solve The Problem, saving the documentation for later. Long
live FORTRAN!
ACKNOWLEGEMENT
--------------
I would like to thank Jan E., Dave S., Rich G., Rich E. for their
help in characterizing the Real Programmer, Heather B. for the
illustration, Kathy E. for putting up with it, and atd!avsdS:mark for the
initial inspriration.
REFERENCES
----------
[1] Feirstein, B., Real Men Don't Eat Quiche, New York, Pocket Books, 1982.
[2] Wirth, N., Algorithms + Datastructures = Programs, Prentice Hall, 1976.
[3] Xerox PARC editors . . .
[4] Finseth, C., Theory and Practice of Text Editors - or - a Cookbook for
an EMACS, B.S. Thesis, MIT/LCS/TM-165, Massachusetts Institute of
Technology, May 1980.
[5] Weinberg, G., The Psychology of Computer Programming, New York, Van
Nostrabd Reinhold, 1971, page 110.
[6] Dijkstra, E., On the GREEN Language Submitted to the DoD, Sigplan
notices, Volume 3, Number 10, October 1978.
[7] Rose, Frank, Joy of Hacking, Science 82, Volume 3, Number 9, November
1982, pages 58 - 66.
[8] The Hacker Papers, Psychology Today, August 1980.