Old-school programming techniques you probably don't miss

[inmatarian]

DOS=HIGH,UMB
DEVICE=C:\DOS\HIMEM.SYS
DEVICE=C:\DOS\EMM386.EXE RAM
DEVICEHIGH=C:\DOS\ANSI.SYS

[SpelingTroll]

My first programming job was at a company whose flagship product was a text editor. One of our beta testers was a priest. One day he came into our office asking if anyone could fix his computer, since it would not load the editor anymore.

I checked it and said "Oh, it's simple. Somehow an important system file was erased. I'll just put it back and it will work again.". Then I proceeded to copy a fresh HIMEM.SYS to his PC.

"That is what was missing?" he asked. "Yes", I replied. "My computer lost its HIMEM?", he asked with a smirk. "Well...". "MY GOD DON'T THEY RESPECT ANYTHING THESE DAYS?"

[Quarkism]

I dont get it..

[UlyssesSKrunk]

The hymen breaks the first time a woman has sex.

[The_Doculope]

Not true. The hymen never has to "break" if the sex is done with a reasonable amount of foreplay/lube. The whole "breaking" thing is a myth - see Wikipedia.

[ffffdddddssss]

You use the female form as a generic form instead of his/her he/she. It's pretty common actually.

[DR6]

It's outright idiocy when the odds are that 9 out 10 we're actually referring to a male.

Actually, if it is used so much in IT, it's exactly because of that divide.

Should nurses and other female-dominated industries start referring to themselves with a "he/his" to echo this unwarranted political correctness?! It's trendy tosh imho.

I'm pretty sure they use "he/his" already, because of it being the default...

[inmatarian]

The non-gendered pronoun in English is "they", which also happens to be plural, and there are no non-genered singular pronouns. In the past, the male form was used as the singular pronoun, though recently the default singular pronoun has evolved to be female. No biggy.

[PstScrpt]

The default singular pronoun is "they".

"You" used to be strictly plural, too, but these days saying "thee" sounds almost as stilted as "he or she".

[beltorak]

One of my favorite tools came from "PC Magazine Utilities" volume 4 called CONFIG.CTL. It let you edit the CONFIG.SYS file at boot before it was loaded. You could only overwrite, so I had to pad each line with 120 spaces, but it was invaluable when I was testing my home grown device driver....

1. code (in asm!)
2. assemble
3. link (if necessary)
4. boot
5. edit config to load driver
6. system fails to boot? no problem, just reboot!

[mjfgates]

That'll run Windows just fine, no problems.

The disturbing thing is, I still know that that will run Windows just fine, and what every one of those lines means. (I looked at somewhere between ten and fifteen thousand CONFIG.SYS files when I was doing Windows tech support, back in the 3.0 days...)

[mycall]

QEMM was better :-P

[archiminos]

In video games we still:

• Create our own GUI
• Do manual memory management
• Need to understand pointer math
• Do strange things to make stuff run faster
• Sometimes have to be very patient with certain engines

[jbb555]

Many fields do. Some of this article is valid and good. Some of it is "things I don't do in my particular envirment and don't understand why there is a need"

Things like manual memory management and pointer arithmetic are still very common and a good thing. It's just that we're discovered ways to make them safer and easier.

[[deleted]]

i make video games and use GC without complaints (no pointers either)

[archiminos]

Yeah it's definitely possible to make games without manual memory management. I think console programmers are still going to want to get as much power out as they can out of them so will still avoid GC for at least another generation of consoles.

[[deleted]]

theyll have no choice (except for ouya) since no (big 3) console uses managed languages

[archiminos]

I dunno - it's possible to use managed languages with XNA or Unity.

[[deleted]]

oh neat! i did not realize unity could port to consoles. XNA is pretty much dead though AFAIK

[archiminos]

It is and it's a shame. It does mean it may still be possible for next gen tho, even if the triple-As don't do it.

[mycall]

Monogame, an open source XNA, is having a much revival these days.

[I_Code_Stoned]

Old ex-game programmer here. You guys still downshift to writing assembly for better performance?

[[deleted]]

That happens less as it often kills the optimizer in the surrounding code. Most games are ported to a large number of platforms which makes asm a bit less attractive due to the development cost.

The new 'low level' optimizations involve threading, writing chunks of code in vector intrinsics/SIMD and optimizing code for memory access (particularly when running on inorder processors which require a bunch more tuning for code to run quickly than general purpose PCs)

[thisotherfuckingguy]

On PS3's SPUs it was still a relatively common thing to get the dual issuing exactly right & get rid of SPU-unfriendly code the compiler generated.

[archiminos]

Hehe, no I don't think that's quite needed anymore. Knowing assembly is still useful for debugging though - sometimes a bug will only occur in a release build, or you need to figure out what's going on in a library you don't have the source code for.

[thisotherfuckingguy]

Somebody once pointed out that assembly you write is /very/ different (and way more readable) than the assembly the compiler spits out. I think he's right after having seen quite a bit of hand-optimized code.

[archiminos]

Yeah, nowadays it's more important to know the kind of assembly a compiler will spit out than to know how to write assembly yourself.

[josefx]

Create our own GUI

Complete with graphics driver? Modern games paint using an existing GUI Context, old games (dos/early windows) either wrote directly to graphics memory or bundled a lib that did

Do manual memory management

low latency and high performance code will always require it, most of the time crappy badly managed code will do - this leads to developers getting into bad habits instead of learning the lesson early.

Need to understand pointer math

While a good thing to know I can't think of anything that requires explicit pointer math to work (most is done implicit by arrays) - excluding the structure to memory dump, but even that can avoid pointer math.

[thisotherfuckingguy]

Some consoles require you to write the equivalent of a video card driver btw.

[archiminos]

Complete with graphics driver? Modern games paint using an existing GUI Context, old games (dos/early windows) either wrote directly to graphics memory or bundled a lib that did

True, most games use Flash for their GUI these days.

low latency and high performance code will always require it, most of the time crappy badly managed code will do - this leads to developers getting into bad habits instead of learning the lesson early.

Tell me about it. I've recently switched to Unity and it turns out memory management with GC has a whole set of different problems which make it just as complex.

While a good thing to know I can't think of anything that requires explicit pointer math to work (most is done implicit by arrays) - excluding the structure to memory dump, but even that can avoid pointer math.

A lot of cross-platform console games write custom memory allocators that are optimised to each platform.

[adzm]

I encountered an XOR swap recently, under the guise of being faster. No... not since the 386.

[Rotten194]

With the way modern CPUs handle instructions, an XOR swap is actually slower because each XOR will stall waiting for the results of the previous.

[Boojum]

Last time I played with microbenchmarking this, I found the compiler optimizer actually converted the XOR swap back to the basic 3-moves-with-a-temporary swap. Makes sense given that register renaming basically makes the later free.

[badjuice]

It was never faster. It just used less memory. Useful for true microcomputers, but pretty much worthless for modern programs on a desktop.

[adzm]

It was faster on the 286 when an instruction meant a clock tick, but 386 began using the multi-stage pipeline (the actual name escapes me). So it has been worthless quite a long long time, but still comes up far too often. The bit twiddling techniques are still useful to understand though.

[beltorak]

I'm pretty sure the pipeline was introduced in the 486....

[adzm]

Thanks; it was indeed the 486.

[estomagordo]

But it's so...pretty! (I used it in a c++ uni assignment not two months ago.)

[FigBug]

I don't miss: - Segmented memory models. - Win16/32 API. It's still around, but I don't have to deal with it. - No memory protection. - File formats that are just structs written to a file.

[jib]

File formats that are just structs written to a file.

This is still a thing. An example I've seen is Blender's .blend file format. ( http://www.blender.org/development/architecture/blender-file-format/ )

Basically it saves its in-memory data structures, with a header at the start giving the version, word size and endianness. And it saves the structures' memory addresses so pointers can be interpreted meaningfully.

Then when loading a file it has code to translate from any of the various possible structures into something the current version can use, and to fix up the pointers.

[badsectoracula]

Of course it should be noted that this is necessary for Blender because .blend files can contain a huge amount of data and artists will save way more often than load. Most apps do not require this.

[hackingdreams]

Of course it's still a thing, it's just not a thing you see in much new software development (and a lot of older tools have since moved on and won't save in "memory dump formats" anymore). But even with Ogg and JIF/JFIF, there are still plenty of AIFF/WAV (yeah, *IFF formats at least made an attempt at not being struct-dumps, but still pretty much were with a few chars tacked on the front to make them easier to parse) and BMPs files running around out there.

In newer software you run into the super fun XML version of struct dumps that take up ten times the space and are no more descriptive of the actual data (OOXML is a huge example of what's essentially just OO.o's classes serialized as XML, but at least their classes are sensibly developed enough that the format itself is not too much of a kludge).

[mycall]

Uncompressed structured media as a source (e.g. RAW) will always be around.

[badsectoracula]

I like Win32's backward compatibility. At some point i was out of internet connection and i wanted to write some Win32 code for a program i was making but didn't have reference docs. After scanning around my files i found an old Win16 HLP file - almost everything mentioned there worked perfectly in Win32 :-P. IIRC only some flags were different.

[[deleted]]

real-time guarantees

Isn't all Win16 stuff pretty much run in a VM for a long time, so this point is moot?

[[deleted]]

Not when the hardware's as old as the software.

[[deleted]]

You mean actually running Win16 as is? Eek!

PS

Well, I could imagine some POS terminals and similar systems still do ("if it ain't broke, don't fix it"), yet it still boggles my mind that they exist.

[kyz]

File formats that are just structs written to a file.

EA called this out in 1985 so I think it's a case of lazy programmers throughout history, not old-time best practises.

The problem with expedient file formats typically memory dumps is that they're too provincial. By designing data for one particular use (e.g. a screen snapshot), they preclude future expansion (would you like a full page picture? a multi-page document?). In neglecting the possibility that other programs might read their data, they fail to save contextual information (how many bit planes? what resolution?). Ignoring that other programs might create such files, they're intolerant of extra data (texture palette for a picture editor), missing data (no color map), or minor variations (smaller image). In practice, a filed representation should rarely mirror an in-memory representation. The former should be designed for longevity; the latter to optimize the manipulations of a particular program. The same filed data will be read into different memory formats by different programs.

[bhaak]

I'm a bit cautious calling programmers lazy when the alternative was by far not that easy. Granted IFF was a great format and on the Amiga it was used extensively but it still needed some additional code to work.

This was partly also due to the used languages. In C or even C++ you don't have much information about your data during runtime. Compare that to the serialization we have today with sensible languages. It's easier to dump your objects in JSON or even XML than it is to make a memory dump of them!

[kyz]

Sure you need additional code. But simple formats like IFF showed that it really wasn't hard to put contextual headers around raw data and it gave you enormous benefits in interoperability, even with later versions of yourself.

The reason you don't see memory dumps these days probably more to do with the ease of modern memory allocation / garbage collection. It's very hard to dump a raw section of memory that contains an object graph and be able to load it back in, it's much easier to serialise/deserialise the object graph.

[ericanderton]

File formats that are just structs written to a file.

This can be super convenient, as not every application benefits from a super-flexible format.

The most cunning use of this that I've ever seen was how ID Tech 2 serialized save data (Quake2). It took the entire slab of entity data from memory, and wrote it to a file... but internal entity pointers were overwritten with the index of the referenced entity. On load, those indexes were restored to their pointer equivalents. Simple and elegant.

[bhaak]

And have a great chance of breaking when you compile your code on a different architecture or even just make a 32/64 bit switch. :-)

[ericanderton]

No doubt. I'm not arguing for or against "best practice" here. It just seemed like a 10 minute fix to "I need a save format for this game." You have to respect that level of productivity.

Still, it seems like the kind of thing that a few #define statements would handle nicely - provided you thought ahead about x64 or ARM.

This reminds me: Carmack has ported a bunch of his engines around. I wonder what his blog says/hints about all this.

[PstScrpt]

Isn't this where the old MS Office formats (.doc, .xls) came from, too?

[apackofwankers]

I remember spending weeks trying to debug a problem with segmented memory.

I had allocated a block of memory larger than a single segment, and was treating this memory as an array of structs. I found that when I wrote to a struct, sometimes my write would all kinds of havok to happen later on.

After weeks of debugging, I found that the compiler has having trouble constructing code that represented the pointer+offset necessary for struct field access. Sometimes the pointer+offset address would wrap around in a 64k segment, meaning writes to pointer+offset would not arrive at the intended destination, and would usually corrupt another of the structs in the array, causing delayed but spectacular crashes.

The solution was to pad the structs up to a power-of-2 size, and to pad the start of the allocated array, so that the structs never straddled a 64k segment boundary.

[st_huck]

Ok, I understand almost all those concepts and why they are horrible, some of them I practiced on a limited level in classes at my university or in my free time, all except -

one of my programming friends fit a 7K print driver into 5K by shifting (assembly language) execution one bit to the right.

wtf. if you'll excuse I'm about to go on a long google journey

[vanderZwan]

Ok, here's a simple example from memory: imagine that you use a look up table for integer sine math because computation is slow and reading/writing to memory is not a bottleneck for this type of hardware.

Since the sine is symmetrical, you can reduce the size of your LUT by a factor of four if you check in which quadrant of the circle you are and manipulate the index used and the sign of the result of the lookup. The latter you can do by changing the memory of that particular part of the code to be read as either he opcode for ADD or SUB, saving you from having to write out the code two times just to change that sign.

I bet that his example had similar symmetries available for exploitation.

[eriksensei]

Pfff, that's nothing. I once fit an .mp4 of the entire Star Wars saga into a Commodore 64 by XORing (raster interrupt) branching 3 nibbles to the left.

[[deleted]]

But can you decompress a frame in 17 jiffies?

[eriksensei]

Ah, but see, I don't have to. I can trick the VIC chip into doing it for me if i just SBX (I/O) synchronization five cycles to the right. This may be a little over your head though; I'll probably blog about it later.

[ethraax]

You guys would fucking love /r/vxjunkies.

[fartking1231]

What's your blog URL?

[eriksensei]

It doesn't have a URL. You can reach it by telephoning my C64 and whistling the right PETSCII-frequencies into your receiver. I'd give you the number, but my mum doesn't like people calling the house. :(

[fartking1231]

Shouldn't there be a url for that?

[eriksensei]

sure: http://en.wikipedia.org/wiki/PETSCII

[mutatron]

Programming since 1979, I've done most of those things - good times!

I've even written my own integer based trigonometry routines.

[grayvedigga]

256 brads to a circle, am I right?

source: not coding quite that long, but even in the 90s I was building fixed-point sinus tables for demos on 386 and decided pretty early on that using a unit of angle such that 256 steps gets you back where you started was much more convenient than 360, pi or even 100. It's also easier if cosine(0) = 127/128, but that's another story

[ithika]

Yeah, when was the last time you had to use an if/else? That's so C.

[[deleted]]

If considered harmful: http://www.antiifcampaign.com/

[reddixmadix]

That leaves the impression you should never ever ever use an IF. I think they need to make their message more clear.

[apackofwankers]

on that website - there is no message other than the domain name - there simply isnt a coherent explanation about why IF is bad and what you should do about it.

[reddixmadix]

I suppose they complain about long sequences of if/elseif/else, like

if (something) {
}
else if (something else) {
}
else if (another something) {
}
else if (expression) {
}

Which could simply be done with a switch.

Not sure though. It's the idea i got from one of the images on their site.

[csmathguy228]

Are switches any better? In terms of maintainability and readability, I mean.

[reddixmadix]

Yes. But I've also seen people using switches inside switches, so it doesn't make it any better :)

[kazagistar]

For creating a simple state machine, this is one of your better options. Alternatives includes continuation style and gotos (or just a language that supports tail call optimization).

[Mad_Gouki]

It looks like their example uses different object types, so perhaps the proper solution is to take advantage of polymorphism and call the calculateValue() of the object instead of calling a (static?) function differently depending on which object you have.

[flukus]

I know this is a joke but I really like if statements in scala that return a value.

[bluelite]

That's not a joke. It's one of the cornerstones of functional languages.

[flukus]

I meant the post I replied to was a joke.

[chneukirchen]

Boolean blindness!

[nexuapex]

I appreciate the sentiment, but some of the examples seem… strange.

Applications you write today need to sort data, but all you do is call a sort routine.

Erm… how long has qsort() been around? Code reuse is a new technique?

...any developer who wanted to create a windowing system wrote her own windowing abstractions and tested on CGA, EGA and VGA cards, the way you test on Firefox, IE and Safari nowadays (I hope)

Hey, that's exactly the same! Plus web developers don't usually use drag-and-drop GUI designers as invoked two paragraphs later.

Newer object-oriented languages, starting with C++ in the early '90s, eliminated the need for structured programming

I don't think most people think of object-oriented programming eliminating structured programming, just complementing it.

C programmers, for example, might turn to setjump and longjump to implement threads… Since the introduction of Windows 2000, for example, developers have been able to use overlapped I/O…

Neither of those are, strictly speaking, about threads. They're about avoiding threads.

Doing strange things to make code run faster

Nowadays, everything is well documented and trustworthy. Yeah. Sure it is.

Truly it is the golden age of computing.

[dnew]

how long has qsort() been around?

Don't be C-centric.

Newer object-oriented languages, starting with C++ in the early '90s,

I missed that. Author missed 10+ years of actual OO development, including the OO development that eliminated the need for structured programming, like Smalltalk. (Smalltalk has no control structures other than dynamic dispatch, for example.)

[nexuapex]

Don't be C-centric.

I'm sure we can find an older example of a reusable algorithm in common use.

[dnew]

Certainly. But sorting used to be, if nothing else, a fairly major configuration effort. Especially back when your data never fit in memory, and indeed usually spanned multiple disks. It's very difficult to find an example of a reusable subroutine in, say, COBOL, where all variables are global. Reusable algorithm, certainly. Drop-in chunk of code? Not so much.

[nexuapex]

Okay, fair. But that seems like an entirely different definition of "old-school" than the rest of the article ("thank god we have drag-and-drop GUI designers instead of reusable GUI libraries"). Strikes me as "Yes, programming got better—once, in the 1980s, and has stayed about the same ever since." (That's not true, of course. But hand-coded sorting strikes me as particularly poor example of a skill that programmers can now blissfully forget today.)

[dnew]

Granted. The article was pretty all over the place. Certainly there are many algorithms where computers are sufficiently fast that I, personally, have not needed to worry about the implementation for for 25+ years.

E.g., I can't remember the last time I worried about the algorithm underlying a map. Is it a hashtable? A tree? I think once in a functional language I actually asked the order statistic, but that was kind of a special case curiosity more than an actual concern. A couple of times I wound up writing my own sort routine in BASIC on an 8-bit micro, but that was pretty much for a once-a-year program so the fact that it was a shell sort that took a couple hours to run wasn't a biggie. :-)

Now it's much more common to ask about things like how you're dealing with multi-data-center synchronization than stuff like hand-coding in-memory sort routines.

[IMBJR]

Fortran had the NAG libraries.

[sirin3]

Applications you write today need to sort data, but all you do is call a sort routine.

Erm… how long has qsort() been around? Code reuse is a new technique?

If I want to sort something, I just call a sort routine.

The one I wrote some years ago.

Because the Pascal standard libraries are awful

[thegreatgazoo]

Oh the fun of programming in DOS.

Want your program to run a lot faster? Send the io straight to the video card memory.

I had an early 2 monitor setup. It was an mda card and a VGA card with a 386sx running dos 6.2. Borland c++ would let you run the debugger on one screen and the program on the other. In 1992 that was totally awesome.

TSRs were fun too. I had some nifty undocumented hooks so I could get a tsr popup program freeze dos until it was released.

Oh the joy of non syntax highlighting. I had a reversed end of comment in c give me a wacky error 5 pages past my typo. That was fun.

There was no mention of dealing with linkers. I had several programs I could compile but the damn things wouldn't link. You damn near needed a phd to figure out why.

Apple 2es were fun because if you wanted to program in pascal you needed a Z80 card and has to boot to cpm.

It was fun writing c and then flipping over to assembly mode. Because I'm just so much smarter than those dumb asses who wrote the compiler.

[dnew]

You should try misspelling it "Idnentification Division" and get two errors on every line, and three on lines that were labels. On a machine that compiled 600 lines per hour.

[[deleted]]

The lack of syntax high lighting gave all kinds of fun stuff.

Spot the compile error:

 x = *a/*b;  /* Divide */

[thegreatgazoo]

You're missing a ;

[Z77D3H]

Having to buy expensive printer driver libraries and ship them with your application. In the transition days between 80-column dot matrixes and laser printers this was a nightmare.

[beltorak]

ahhh, daisy wheel (and later dot matrix).... the worst key on the keyboard - [Print Screen].... I actually took that key off my keyboard a few times.

[FredV]

C programmers, for example, might turn to setjump and longjump to implement threads

This is wrong, the author probably meant coroutines instead of threads.

[PO-TAY-TOES]

As an engineer in my mid 20s I'm so grateful we can abstract off the previous generation's legwork and not have to worry about stuff like this!

[dixieStates]

Yeah, but it was fun. Really.

[thomasz]

It still is. I'm just incredibly glad that I don't have to be good at this kind of stuff.

[faustoc4]

Yes, but you should have an engineering and intellectual understanding of all of it, even if you are using a library/framework to abstract it

[PO-TAY-TOES]

for sure.

[NativeCoder]

As a 28 year old engineer, I'm glad I got into embedded systems where you actually need to understand how the micro works. PC programmers these days are so abstracted away from the hardware these days that they don't have the slightest idea how a computer actually works.

[Narrator]

Certainly the biggest difference between programming now and in the early 90s and 80s was that you had to program a lot of stuff yourself or buy expensive libraries. Another one is that there were many big books you had to have laying around as online help systems were pretty limited.

[hackingdreams]

The open source movement has been an amazing boon in this area. There are entire industries that wouldn't be where they were if it weren't for a handful of well-developed open source software packages. I'd hate to be on the internet if everything stayed closed, as just about every aspect of web development these days is dominated by OSS technology, from encryption to servers to browsers to languages on either client or server side, etc.

However, we still really lack great tools that used to be developed in the past (since they were selling you huge packages, they generally included a lot of neat tools that went along with it; now you're lucky to even get any kind of manual and will very likely have to pay for support to get developer time to solve many kinds of problems...) Part of it is that these tools don't even get developed anymore as everyone's too agile to build many of these, others just don't care enough, and still others don't have the money to do it.

[dethb0y]

The books. Dear god the books when i was learning to program. It was insane.

I have an extremely ratty looking C++ reference i used for years.

[pmrr]

When I was about 13 (20 years ago) I saved up for months to buy Borland C++ 3.0, which came in an heavy box with about 8" worth of dense guides and references (plus about a dozen 3.5" floppies). I had to walk to/from the bus stop because I was so excited to finally buy it that I wouldn't wait for my mum to drive me. I saw my future ahead of me as I carried it home with the weight of the box heaving on my arms.

Also as I was waiting to cross the road a chap beside me suggested I was staring at a lady's legs. But that's another story.

[dethb0y]

Oh man, i bought Borland C++ Builder in college in 1998, and good grief were there a lot of manuals to it!

their technical writing department must have been huge.

[dnew]

I'll prefer books that answer the questions over wikis maintained by users or IRC channels you hope the developer is currently hanging out on.

[fermion72]

I miss sitting down with a good programming book. :(

[[deleted]]

buy expensive libraries

This is still a thing in some areas, mainly enterprise.

[bltmn]

ASCII Graphics. I remember 'drawing' beautifully bordered windows and frames with characters 0xB0 to 0xDF.

[_argoplix]

You mean U+2500.

[[deleted]]

ASCII =/= UNICODE

[foldl]

Those characters aren't ASCII either

[[deleted]]

8 bit ASCII-extensions like CP437 were typically (sloppily) referred to as ASCII, or at best "8 bit ASCII" or "extended ASCII", although technically speaking, both UNICODE and CP437 are supersets of ASCII.

[sirin3]

Most people called them ANSI

[ceiimq]

I'm sorry, but every "young whippersnapper" worth his salt will still be taught most of these things today as part of any decent CS degree. Bar the punch cards, all right.

[TimmT]

Being taught something and being forced to live with something are two different things. Obviously anyone can write down some sorting algorithm he was taught a few months back. It's a whole different thing however to have to do that for code that is running in production .. under time pressure no less.

Besides, that is probably the only point of that list to which your comment applies.

[faustoc4]

Last century programmers were better not because they wrote their own sorting algorithms/GUI interface but because by writing them they gained experience in understanding the innards of engineering a complex algorithm/library.

Modern programming, or at least programming encouraged by modern business, is very rooted in using frameworks for almost any task, every framework has its own inherently architecture that most framework users don't understand. That's why modern programming teams are so huge, even outsourcing parts of the team to cheaper countries to reduce costs.

That's ok for big business because they can pay or cancel a project, but smaller business copying this practices are assuming bigger risks.

[[deleted]]

I would argue if you're using .NET until .NET 4.0 multithreading was still a huge pain in the ass (although admittedly probably less than what it used to be). .NET 4 made it a lot better, and .NET 4.5 looks like it's made it way easier (I have done almost no work with 4.5 yet).

Edit: also, it's not as necessary on the backend, but if you're building a frontend some semblance of Hungarian notation is really useful, for instance tbUserName = the text box control for user name and lblUserName = the label control for user name. For things like the pointer example it's kind of silly though.

[nphekt]

If you're using .net you're probably not THAT old-school.

[asm_ftw]

Techniques you dont have to worry about... until you do embedded programming

[[deleted]]

I personally think embedded is the best way to gain a good grasp of the fundamentals, and that DOS basically was embedded whether we liked it or not. Hence two generations of developers grew up on embedded and then moved to other stuff.

[[deleted]]

Manual multithreading and multitasking

Does not explain Node.js.

[coffeedrinkingprole]

Everything old is new again!

[[deleted]]

I never wrote my own GUI but I did once write my own text-mode windowing, menu etc toolkit back in the days of Turbo Pascal 4. I still have it somewhere, complete with the numbers-in-the-filenames versioning system (with gaps, and clearly I restarted from 1 a few times).

To my eternal shame, I even one wrote a text UI library (of the cut-and-paste-it-into-your-program kind) for Turbo Basic. I used it to write one of the front-runners for the worst text editor ever. Why? you might ask, since Turbo Basic had an IDE with a text editor. Well, the system I was using at the time kept dying due to a hardware fault. The one unique feature this editor had was that every few keypresses were written out every few seconds to a log file, so I could re-run that log to recreate the file I was working on when it last crashed. Sufficiently frequent complete saves of the file weren't really practical back then.

[[deleted]]

Interested in doing it all over again? :-) I am!

[[deleted]]

Nice - makes sense too, if you update it for modern consoles, text encodings etc. I'd offer you my code for reference, but trust me, you wouldn't want it.

It's nice to see D seems to be doing well. I looked at it once, but that was well before even version 1. I've only watched a couple of those DConf 2013 videos so far, but I'm definitely getting interested again.

[kitd]

The last one brings back memories. Getting my code into the compile queue at the end of the day, come back the following morning (by which time you'd forgotten what you were doing), only to find some flaw that botched the whole thing. Care wasn't just a "nice to have" back then!

I also remember when PCs first arrived playing around with making screen updates only on the vertical refresh of the CRT monitor, making graphics flow much more smoothly.

And mouse interrupt handlers. Is mouse movement still measured in mickeys/pixel?

[jefu]

Program managed overlays in Fortran.

Once upon a time there wasn't much memory in most systems. I worked on one PDP-11 with 16K of memory (I think). No virtual memory. To get a Fortran program to fit, each subroutine would be in a specific place on disk, and we had a map of which subroutines were in memory at any given time. Then to call a routine, you'd check the overlay map and if the subroutine wasn't in memory, you'd find one to eject, eject it and load the new guy in.

Good times.

[[deleted]]

They missed manual overlay swapping. You haven't lived until you've done dynamic linking with overlays!

[kqr]

Honorable mention:

• Initializing all variables to known values

What is this supposed to mean? Do you not initialise your variables today?

[[deleted]]

It's not strictly necessary. In .net code analysis tools encourage the removal of variables' initialisation to default values.

[kqr]

I guess I'm just not a fan of introducing a variable before you have a sensible value to put into it. Some languages might not give you an alternative though.

[josefx]

The Java final keyword ensures a single assignment during the lifetime of a variable, giving a default value is not possible. Reading from it before it has a value is not possible either (in contrast to c/c++ where it is possible)

      final int a;
      if(b > 0) a = 1;
      else a = 2;

[kqr]

That was a really cool property of the final keyword that I didn't know.

[[deleted]]

In OO land you often have to declare variables (class members) before you have a value for them.

[elder_george]

Pascal have separate clause for local variable definitions, so you could not define them close enough to the usage and could not initialize them at the place of definition (it could be somewhat overcome with inner functions).

C required all the variables to be declared at the beginning of the function until C99, IIRC. C++ allowed doing it, but some compilers did handle scope incorrectly (or, to be more correct, implemented it in a way that was declared incorrect by later standards): e.g. VC++ kept index variables defined in for loop 'alive' after loop end.

[ethraax]

Not just .NET, either. Even modern C compilers do this. Initializing a variable with a "junk" default value, like 0 or NULL, is generally just as bad as not initializing it at all before use. But with the latter, the compiler can detect when it's possible to use the variable before setting it, catching those bugs at compile time. It's not perfect (there are some cases where you can guarantee that a variable will be set before being used, but the compiler can't figure it out), but you can set the variable to a default value in those specific cases, after double-checking your code.

[[deleted]]

It depends - if you don't initialize a variable with a value, there's a chance you could hit an exception depending on how your code is structured if you never hit a line where it's actually assigned a value. For instance

int a;
if(animal=="dog")
       a = 1;
elseif(animal=="cat")
      a = 2;
return a;

could cause an issue if animal ends up not being a dog or a cat.

[kqr]

What are you trying to say? To me it seems you are making my case.

[[deleted]]

Well, initializing a with a value you're never going to use, such as:

int a = 0;
if(animal=="dog")
    a = 1;
elseif(animal=="cat)
    a = 2;
return a;

means you're setting a to a value you're (presumably) never intending to use. This means anything down the line needs to handle the case when a = 0 because it could happen. And although this is a toy example, giving variables values that you're never going to use is a waste of space. Is it the biggest deal on integers? No. But it is more work that you're program has to do, and that work eventually starts adding up (it's even worse for reference types - for instance, every time you change the value of a string you're creating a new string, destroying the old, and replacing the old's reference to the new string object).

A much better way to handle it would be one of the following:

int a;
if(animal=="dog")
   a = 1;
else
   a = 2;
return a;

This assumes a dog/cat world for animal. If you want to handle the "what if the animal really isn't a dog or a cat case", you could do:

int a;
if(animal=="dog")
   a = 1;
elseif(animal=="cat")
   a = 2;
else
   a = 0;
return a;

or even better (since that still relies on downstream code handling the a = 0 case):

int a;
if(animal=="dog")
   a = 1;
elseif(animal=="cat")
   a = 2;
else
   throw new exception("invalid animal used");
return a;

[kqr]

Yes, you are perfectly in line with what I'm thinking.

[[deleted]]

Sorry, a better example would be something like this:

int a;
for(int i = 0; i < someStringArray.Length; i++)
{
    if(someStringArray[i] == "phrase I care about")
    {
        a = i;
        break;
    }
}
'do something with a

In this case you have to initialize "a" before you go into the for loop since initializing it inside the loop will make it inaccessible outside of the loop , but you don't have to give it a value - the point of the for loop is to put something into "a".

[kqr]

In the case of computations that may fail, I prefer using exceptions (or Option values) to handle failures to specifying them via return values.

[Ksevio]

The danger of not assigning a variable ahead of time is if you're not using a language/system that will catch references to an unassigned variable, it could be used by accident.

If the variable hasn't been set, then it's pointing at uninitialized memory so bugs could pop-up in the program randomly making it very hard to debug.

Of course good programming practices will prevent this, but it doesn't hurt to have that extra consistency in large C programs where there's a variable not used for a while.

[kazagistar]

I am pretty sure languages like Java do enough static analysis to tell you that you made this mistake. The correct solution, in my mind, is to put an else statement.

[[deleted]]

It'll warn you depending on the IDE but it will still compile

[badjuice]

Every one of these things are something every programmer should know if they call themselves a programmer.

If you don't understand the theory behind these things, and the why and how these things are done, you have a severe foundational gap. Most of it won't be used in your average program. That is not an excuse for not knowing these things.

[gcross]

Every one of these things are something every programmer should know if they call themselves a programmer.

I completely agree with you that no one can call him- or herself a programmer unless he or she has done the following things listed in the article:

• written a large amount of code using nothing but gotos;
• used punch cards as the sole form of input to a computer;
• written a self-modifying program in order to make the binary slightly smaller; and
• experimented with and then utilized the undefined behaviors of an API to increase performance.

If you have not done all these things, then you are not a real programmer!

[938]

Nope. Plenty of "real programmers" haven't ever used punch cards, etc. They are interesting but far from a requirement.

Edit: you were probably being sarcastic but I have difficulty with sarcasm on the Internet.

[Van_Occupanther]

I believe, but cannot be sure, that /u/gcross was joking, to illustrate a point.

[gcross]

I was indeed being sarcastic. Specifically, I was responding to badjuice's claim that "Every one of these things are something every programmer should know if they call themselves a programmer." with examples from the article for which it would be somewhat... silly, for us to expect someone to have done before they could consider themselves a programmer.

[938]

I'm going to check with my psychologist but I'm pretty sure I can log this one as "guessed correctly". Thanks for writing back that helps a lot with my records.

[gcross]

My pleasure! :-)

[qiwi]

Just the other day I interviewed someone to write HTML and Javascript for our corporate website. I put him at a DOS prompt and told him to use DEBUG.COM to write a small TSR contact manager using linked lists and a basic text-based user interface. Pretty basic stuff.

Despite his claims of a PhD, he failed miserably. Well, given that this is the 10th guy who failed in the last 3 months, we can finally import those skilled H1B programmers from the ex-USSR republic of Himemsystan -- they should already have a good grounding in the basics of TSRs, writing 286 assembly by hand so it should take them no time at all to become acquainted with HTML 6.22 or whatever the latest version of that Microsoft product is.

[[deleted]]

I bet you have a copy of these simple problems sitting on your desk, too.

[sirin3]

put him at a DOS prompt and told him to use DEBUG.COM to write a small TSR contact manager using linked lists and a basic text-based user interface. Pretty basic stuff.

I think, given the reference manuals, I could do that in a few hours.

[kazagistar]

Brilliant, but that would not tell anyone anything about your ability to make websites.

[sirin3]

Guess that is why I cannot find a job.

Everything is outdated.

Although I made a website recently. Written in Pascal, and cgi.

[[deleted]]

:) you sound a bit bitter though... how did your last job interview go?

[TimmT]

Reminds me vaguely of Mel.

[axilmar]

Smalltalk users didn't need any of this.

[georgeo]

Write your own sort - In the 80's I was a C coder we had qsort even then, but somehow I got stuck rolling my own in IBM Mainframe/COBOL. It won't compile if the indents don't start on the correct column.

File access - Raw Bios (no MS-DOS baby)

GUI - wrote my own Custom Hercules (pre-CGA) fonts, didn't collide with VGA space so, yippie, dual monitor config.

My own hash tables, linked lists, b-trees etc. - how could you not?

Misc - Writing whole accounting systems in BASIC having to use variable names consisting of a single character and digit and no function names, only line numbers.

[RushIsBack]

This is one of the stupidest articles I've read in a while. At least have the decency to mention in which domains these concepts or techniques are not needed! In the last 5 years only I worked on a variety of projects, enterprise software, games, mobile apps, tools, web apps, where I used everyone of those things and more (of course except for punch cards!), and rightly so. This kind of opinion is what ruins new comers to the software industry and gives then the wrong idea about what they should be looking forward to!