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Comment by jstimpfle | Hacker News Reader

"Python for C programmers" would probably make much more sense (following "C for Assembly programmers").

I agree. My computer science classes were taught almost entirely in C. Learning C-like languages is pretty easy, but I constantly feel like I'm using Python incorrectly. I feel like I'm trying to take what is elegant in C and implement it in Python, even though what is elegant in Python is very different.

I think it's largely the opposite for current students. My university's CS program is taught entirely using Python and other higher level languages. CS students here don't have to learn C at all anymore; if you want to learn C here, you have to get a Computer Engineering degree.

Aren't most OS courses taught in C? At least two years ago when I took operating systems (in the US) we had to hack up Linux source in C.

Edit: And thinking on it our computer graphics course was in C++ (yea yea C != C++).

Most OS are written in C. Thus to interface to get good use from the OS you use the libraries which are in C.. (To get networking, shared memory, message passing, process scheduling and all that good stuff).

I wrote c wrappers for ada, and it was a pain. Much easier to use C (or C++) to get to OS functionality.

As long as OS are written in C, it will be with us. Also useful for embedded.

see: /usr/include

There's a huge variety in CS programs and you can't really assume anything about the languages they all use. My understanding is that accreditation for CS degree programs is based on concepts, not implementation details like programming language.

My OS class (a while ago) used assembly language for a simple VM, with one or two assignments requiring us to modify the VM itself to implement new instructions required for new OS features (task switching, virtual memory, etc.).

A lot of CS programs aren't even accredited. My (highly ranked US university) doesn't have any accreditation for the CS program.

OS (or computer graphics) courses aren't necessarily mandatory for CS degrees. In fact, if I'd put my mind to it, I'm pretty sure I could have gotten a CS degree without too much programming at all by loading up on as many math and theory courses as possible.

Personally I did study C via a couple of electrical engineering courses I took.

At the same time, understanding the underlying ideas of memory management, process isolation, IPC, IO/CPU sharing is really, really useful for not making silly mistakes.

Oh absolutely. My point was mainly that just having a CS degree isn't a guarantee of, well, anything really.

While we used some C for manipulating kernel stuff, we implemented a lot of the algorithms in Python since it let us do multi threading, multi processing, signals and a couple of others and my college uses a lot of Python...A bit too much Python now that I think about it.

I've heard many colleges have switched to Python for Comp Sci. I've seen linear algebra and computer graphics courses done in Python, too (including writing a ray tracer). The goal is learn the concept without the language getting in the way. Performance isn't a big concern (with poor performance you can still play with sparse data structures and other optimizations).

While I imagine it was good to get familiar with writing C, even assignments for operating systems classes didn't have all of the performance concerns or strict checking that production code would, right? (but C still is probably the best choice for other reasons in an OS class)

My undergrad OS course was taught in Java shudder. It was a very theory heavy class, and the only code we actually wrote was a toy scheduling algorithm.

CS50 used C almost exclusively, that was very recent.

It really depends on the school you attend. The CS program at my school was very theory heavy, and light on programming. The entire department used (and still uses) C because you can use it for every class and every professor knew it. I think from a computer science perspective, C was preferred because you have very low-level control and it is a very verbose language where everything is performed explicitly.

Interesting. My college used a lot of Python for nearly all the classes except for language seminars and some parts of other classes.

I asked my professors why and they argued that Python "doesn't get in the way" (static typing, compilation etc.) allowing us to focus more on learning the algorithms and theory.

I think I'd prefer to use Python in most cases. My data structures class was taught by a professor who LOVED a ten year old book. Unfortunately, more than half of the assignments in the book wouldn't compile with GCC. Everyone I know who took that class said it was the hardest class they took in college because you basically had to rewrite every program from scratch.

I still preferred C to Java. I'm sure Python would have made that class way easier, though I do love pointers.

Why not "Assembly for C programmers"? I would say both are useful directions.

I've written a Python for Java programmers book - http://antrix.net/py4java

Do you have a link to C for Assembly Programmers? A google search doesn't turn up anything.

It was just an idea. C is as low as most people bother to go these days.

"C For Assembly Programmers" would an interesting read. I've looked at some mission-critical C code before, where much of the language is abandoned in favor of "safety"; in those cases I got the feeling that C was being used as little more than an Assembly preprocessor.

Most books from the early days were essentially that, although they weren't called that because it was just assumed. The K&R is, in a way, even if it doesn't mention assembly. It's obvious to see how a for loop relates to the assembly instructions (of course it isn't today, with all the trickery compilers do underneath).

Yeah, K&R assumes at least some familiarity with assembly programming - it uses assembly-level terms like "address" and "register", without ever defining what they mean. The chapter on pointers starts out with:

"A pointer is a variable that contains the address of another variable." [1st edition, 1978]

But how do you learn assembly?

Assembly Programming for Chip Designers

You can actually inline assembly into your C code. I think this could be the easiest way to practice it.

I learned basic 16 bit x86 assembly by making simple COM executables and boot sectors with MASM. I don't know if its still possible run COM on modern Windows (this was in the 32 bit XP days), but getting started with boot sectors using BIOS interrupt service routines for IO should be an interesting project. You should be able to use the assembler output directly in a VM as a disk image this way, or dd it to something and watch it run on bare metal.

There are lots of tutorials on the web. For example,

https://en.wikibooks.org/wiki/X86_Assembly

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