Comment by o2sd | Hacker News Reader

Comment by o2sd | Hacker News Reader

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> If you're passionate about computing and software engineering, you'll have a natural interest in how things work under the hood.

When I was 12, I learned 6502 assembly language. The computer I had did not have a C compiler, only BASIC or assembler (you could also enter hex into memory locations, which was hardcore). Learning assembly is actually a LOT easier than people make out. Assembly is basically mnemonics for the underlying machine code, plus named locations. Assembly has everything a language needs for Turing completeness. Assign, Add, Subtract, Compare, Branch. And THAT is how the computer works 'under the hood'. C is one level of abstraction above that, and while it's true that a LOT of software has been historically written in C, before C came along, most software was written in assembler or BASIC (which is older than C, for the historians).

> Learning C is almost mandatory if you want to see how deep the rabbit hole is.

Not really. I know what is going on 'down there', regardless of which language was used to compile the machine code. What is REALLY useful is to have really succinct, powerful, high-level abstractions to build software quickly and with as little code as possible.

> Knowing it will certainly help when exploring the intricacies of processors and operating systems.

If that's what you want to do, then fine. I'm too much of a utilitarian for that kind of exploration. I want to build stuff.

I think if you want to understand what's going on 'down there' in the 'rabbit hole', learn assembly language. There are only seven to ten basic instructions and you can learn them in a couple of days. You can build anything you want in assembly language, if you have an eternity to do it in.

> Assembly has everything a language needs for Turing completeness. Assign, Add, Subtract, Compare, Branch. And THAT is how the computer works 'under the hood'.

While what you say about Assembly is true, there's more to computer internals than doing arithmetic and control flow in the CPU. Virtual memory, DMA and IO are equally important, and the code that deals with that stuff is usually C code.

> > Learning C is almost mandatory if you want to see how deep the rabbit hole is. > Not really. I know what is going on 'down there', regardless of which language was used to compile the machine code. What is REALLY useful is to have really succinct, powerful, high-level abstractions to build software quickly and with as little code as possible.

You can book-learn what's going on under the hood but that's no replacement for getting your hands dirty. If you want to actually write code that uses memory and pointers (e.g. memory mapped files), runs in kernel mode or twiddles with page tables and virtual memory, C is the best language you can do it with.

> I think if you want to understand what's going on 'down there' in the 'rabbit hole', learn assembly language.

Learning Assembly language(s) is a very useful skill for everyone. But doing anything practical with Assembly is a futile effort, it's best to stick to C in low level stuff and resort to Assembly only when you absolutely have to. For example when you have to change between processor modes or write an interrupt handler routing, there must be some (inline) Assembly involved. But if you want to get stuff done and work with the interesting stuff, going all-assembly is not worth the effort.

I wrote a tiny multitasking operating system in Assembly. While it worked very well initially, as soon as the complexity went above one screenful of assembly, it started becoming very unwieldy. I moved on to C and got more stuff done. I could focus on the interesting stuff like scheduling algorithms and virtual memory when I didn't have the mental overhead of having to make register allocations manually or whipping up my own control structures.

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