Real Programmers Don't Write Pascal

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Real Programmers Don't Write Pascal

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Back in the good old days - the "Golden Era" of computers, it was easy to separate the real men from the boys (sometimes 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 who didn't. A real computer programmer said things like:

DO 10 I=1,10

and:

ABEND

They talked in capital letters, you understand. 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 an Pac-Man, and anyone can buy and understand their very own personal computer. The Real Programmer is in danger of becoming extinct, of being replaced by high-school students with TRS-80's.

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 to 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 very 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 call me by name, pronouncing it `Veert', or you can call me by value, `Worth'." One can tell immediately from this comment that Nicklaus Wirth is a Quiche Eater. The only parameter passing mechanism that Real Programmers endorse is "call by value-return", as implemented in the IBM/370 FORTRAN G and H compilers. Real Programmers don't need all those 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 Programming:

• Real Programmers aren't afraid to use GOTO's.
• 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, all those structures can be simulated, when necessary, by using assigned GOTO's.

Data Structures have also gotten a lot of press lately. Abstract Data Types, Structures, Pointers, Lists, and Strings have become popular in certain circles. Nicklaus Wirth (the aforementioned Quiche Eater) actually managed to write an entire book [2] contending that you could write a program based on Data Structures, instead of the other way round. As all Real Programmers know, the only useful Data Structure is the ARRAY. Strings, Lists, Structures, and Sets - they are all just special cases of Arrays and can be treated that way just as easily without messing up your programming 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 does the Real Programmer use? CP/M? God forbid - CP/M, after all, is basically a toy operating system. Even little old ladies and grade school students can use and understand 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 the JCL manual. A great programmer can write JCL without referring to the JCL manual at all. A truly outstanding programmer can find bugs buried in a six-Megabyte core dump without using a hex calculator (I have actually seen this done).

OS/370 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 that 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 his program destroyed the bootstrap. 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 best forgotten. Legend has it that Seymour Cray (who invented the Cray-1 supercomputer, and most of Control Data's computers) actually toggled the first operating system for the CDC-7600 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 system programmer at 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 telephone, 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 telephone. The moral of the story: while a Real Programmer usually includes a keypunch and a 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 O29 keypunch. In fact, the building I work in doesn't contain a single keypunch. The Real Programmer in this situation has to work with a "text editor" program. Most systems supply several text editors to select from, and Real Programmers 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 use a computer whose operating system is called SmallTalk, and would certainly never talk to the computer with a mouse.

Some of the concepts in these Xerox editors have been incorporated into editors running on more reasonable operating systems - EMACS and VI being two. The problem with these editors is that Real Programmers consider "what you see is what you get" is just a bad concept in Text Editing as it is in women. No, the Real Programmer wants a "you asked for it, you got it" text editor - complicated, cryptic, powerful, unforgiving, and 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 in your name 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 subtile 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 instead 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 even thinks of sending anyone 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".

Here are some programming tools that Real Programmers don't use:

• FORTRAN preprocessors like MORTRAN and RATFOR. These are the Cuisinarts of programming - great for making Quiche. See the 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 the EQUIVALENCE statement, and make it impossible to modify the operating system code with negative subscripts. Worst of all, bounds checking is inefficient.
• Source code maintenance systems. A Real Programmer keeps the code locked up in a card file, because it implies that the owner cannot leave 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-1 supercomputers.
• Real Programmers work for National Security Agency, decoding Russian transmissions.
• It was largely due to the efforts of thousands of Real Programmers working at NASA that our boys got to the moon and back before the Russkies.
• Real Programmers programmed the computers in the Space Shuttle.
• Real Programmers are at work for Boing, designing the operating system 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 took a pattern-matching program into a few hundred bytes of unused memory in Voyager spacecraft that searched for, located, and photographed a new moon of Jupiter.

The current plan for Galileo spacecraft is to use a gravity-assist trajectory past Mars on the way to Jupiter. This trajectory passes 80±3 kilometers of the surface of Mars. Nobody is going to trust a Pascal program (or a Pascal programmer for that matter) for navigation to those 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 Programmers' 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 (a DoD). For a while, it seemed that Ada was destined to become a language which 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 which the DoD adopted has enough interesting features to make it approachable - it's incredibly complex, includes methods for messing with the operating system and rearranging memory, and Edsger Dijkstra doesn't like it [6]. Dijkstra, as I'm sure you know, was the author of "The Go To Considered Harmful" - a landmark work in programming methologie, applauded by Pascal Programmers and Quiche Eaters alike. Besides, the determined Real Programmer can write FORTRAN programs in any language.

Real Programmers might compromise their 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 writing video games at Atari, for example (but not playing them - a Real Programmer knows how to beat the machine every time - no challenge in that). Everybody 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, mainly because nobody has found a use for Computer Graphics yet. On the other hand, all Computer Graphics programming is done in FORTRAN, so there are a fair number of 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 as he works - with computers. The Real Programmer is constantly amazed that his employer actually pays him for what he would be doing for fun anyway (although he is careful not to express this opinion out loud). Occasionally, a 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 a simulation 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 in best? This is an important question for managers of Real Programmers. Considering the amount of money it costs to keep a Real Programmer on the staff, it's best to put him or her in an environment where they can actually get the work done.

The typical Real Programmer lives in front of a computer terminal. Surrounding this terminal are:

• Listings of all the 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 buts floating in the coffee. In some cases, the cups will contain Orange Crush.
• Unless the Real Programmer is very good, there will be copies of the OS JCL manual and Principals of Operation open at some particularly interestin pages.
• Taped on the wall is a line-printer Snoopy calendar for the year 1969.
• Strewn about the floor are several wrappers for peanut buffer filled cheese bars - of the type that are made pre-stale at the bakery so that 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 dubble-stuff Oleos for special occasions.
• Underneath the Oleos is a flow-charting template, left there by the previous occupant of the office. Real Programmers write programs, not documentation - leave that to the maintenance people.

The Real Programmer is capable of working thirty, forty, even fifty hours at a stretch, under intense pressure. In fact, the Real Programmer prefers it that way. Bad response time doesn't bother the Real Programmer - it provides the 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 fifty-hour marathons. This not only impresses the hell out of the Real Programmers manager, who was despairing of ever getting the project done at time, but also creates a convenient excuse for not doing the documentation. In general:

• No Real Programmer works nine to five (unless its the ones at night).
• A Real Programmer might or might not know the name of their spouse. The Real Programmer does, however, know the entire EBCDIC (or ASCII) code table.
• Real Programmers don't know how to cook. Grocery stores aren't open at three o'clock 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 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 subtile tricks, like adding structured programming constructs to FROTRAN, 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 to a FORTRAN-66 compiler at the drop of an option card - to compile DO loops the way God intended.

Even UNIX might not be as hard to Real Programmers at 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, and virtual memory. If you ignore the fact that it's structured, even C programming can be appreciated by Real Programmers. 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 even talking about #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 ill-defined goals, bizzare 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!

REFERENCES

• [1] Feirstein, B., Real Men Don't Eat Quiche, New York, Pocket Books, 1982.
• [2] Wirth, N., Algorithms + Data Structures = Programs, Prentice Hall 1976.
• [3] Xerox PARC editors...
• [4] Finseth, C., Therory 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 Nostrand 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.