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I think it's time for you to read a text book about virtual memory and page tables. There's a lot going on under the hood.

The short answer is, every process lives in its own virtual space, which appears to the process to be the whole of system memory. For that process, the only things that exist are its own memory and the kernel parts which are mapped into it. The only way a process can see other process memory is via the kernel.

The longer answer is that the way the kernel achieves is this is through a couple of bits of hardware in particular the MMU (memory management unit) which includes the TLB (translation lookaside buffer). The TLB is a kind of cache that handles fast lookups from virtual addresses (that a process sees), to physical addresses (that the kernel sees and manages). A TLB lookup will fail if a process tries to access a virtual address that is not mapped into it. In this case, the kernel (or on x86, the MMU on behalf of the kernel) will consult a bunch of tables ("page tables") to find the mapping and load it. If the kernel can't find the memory, then your process is trying to access memory that was never allocated to it, and you get a segfault (the memory segment couldn't be found).

There's a lot to it, and a single reddit comment isn't the place to get into all the details. I'd take a look at Modern Operating Systems or any other decent text book for a full explanation.

The C bible (also called K&R for its authors Kernighan and Ritchie respectively) is absolutely essential for learning C. Ritchie knew C better than anyone (for obvious reasons) and it’s examples are very well done thanks to Kernighan’s genius. The syntax may be slightly dated in some places, but it’s principles/advice are timeless.

https://www.amazon.com/Programming-Language-2nd-Brian-Kernighan/dp/0131103628

It's quaint that you think that, but you really shouldn't.

Never assume a variable is set if it isn't expressly set. Variables declared as statics or globals are likely initialized, but variables defined on the stack (local variables) aren't going to be.

Building your code in debug mode will often initialize memory for you to help you identify problems (MSFT VS used to use 0xAA55 or something similar for this) but when you do a release build, that helper goes out the window.

And, like I said, in this particular case it doesn't matter, but a Lint check will complain.

The link should go to slide 65 which discusses this:
https://www.slideshare.net/olvemaudal/deep-c/65-include_stdioh_eh_is_it

Just thought of something else: http://cppcheck.sourceforge.net/

You can try running this on your source. Fuzzers like this tell you when you did something legal but is usually indicative of a problem, like going to the casino at 8am.

As you said, header files are used to share code between your files. They are also useful in keeping your code well structured. Header files usually contain includes to all needed libraries, function declarations as well as macros to be shared across your files. As long as you #include the header file in your .c file, everything in the header file can be used as is.

Speaking of macros, I personally love them. It depends on how complex your code gets, but if you're using hardcoded values at any point, macros will make your code a lot more readable. Compare

void eat_cookies(int cookies_eaten) { if (cookies_eaten >= 20) { printf("No more cookies for you!"); } else { printf("Here, have a cookie!"); } } to

void eat_cookies(int cookies_eaten) { if (cookies_eaten >= MAX_COOKIES) { printf("No more cookies for you!"); } else { printf("Here, have a cookie!"); } } (Probably not the best example, but I hope you see where I'm going with this)

Apart from that, macros make maintaining the code a lot easier as well. Instead of having to change hardcoded values everywhere they appear in your files, you can just change the macro in the header file and be good to go.

Lastly, in order to use functions across your files, the function declaration has to be in your header like this:

void eat_cookies(int cookies_eaten);

I must be really new to programming cause I don't know what a storyboard is! I just finished a C programming class this fall, so I just know the basics so far. I mostly want a replacement for LiveSplit (http://livesplit.org/) that can be run in the terminal.

You can do C development in Eclipse on Linux/MacOS/Windows with the CDT. Under MacOS, you can also use Xcode. If you're willing to pay for a commercial IDE (and willing to use CMake), CLion is an excellent cross-platform option: https://www.jetbrains.com/clion/

I don't use IDEs much, I'm partial to Sublime Text and a terminal, but I can give some suggestions.

If you're looking for a C IDE, I recommend CodeBlocks. It's a nice IDE with quite a few features.

If you're looking for a C++ IDE, I would go with Xamarin. It's extremely similar to VS, and I would recommend the hell out of it.

Honestly though, Sublime Text with some extensions and plugins and a terminal would do you just fine for some basic programming. Hell, I've got a pretty complex (for me) project I'm working on and I'm ONLY using Sublime.

Good luck with your class!

The C Programming Language may be downloaded for free, a quick search returned this link: http://www.cimat.mx/ciencia_para_jovenes/bachillerato/libros/[Kernighan-Ritchie]The_C_Programming_Language.pdf

It's dense; but if you want to really learn the basics of C, nothing compares.

From the book "The C Programming Language" (B. Kernighan and D. Ritchie), section 3.8 ("Goto and Labels"):

> Code involving a goto can always be written without one, though perhaps at the price of some repeated tests or an extra variable

and later

> With a few exceptions [...] code that relies on goto statements is generally harder to understand and to maintain [...], it does seem that goto statements should be used rarely, if at all.

With this wisdom is how I grew up. It's not a sin, it's just bad manners.

If you don't have any specific questions for us here, The C Programming Language, co-authored by the creator of C, is the gold standard in books about the language.

I'm working my way through Kernighan and Ritchie's "The C Programming Language". This appears to be the authority on C. It's not friendly for a total beginner, but if you have some experience, it's pretty amazing.

I got curious and looked at the (free) PDF https://freecomputerbooks.com/Modern-C-by-Jens-Gustedt.html

That's not math... The 1st challenge is basically just a few basic multiplication and a few conditional branching.

THIS is complex math https://www.amazon.com/Mathematics-Machine-Learning-Peter-Deisenroth/dp/110845514X/

I mean you can't learn C in 4-5 days having no programming experience. If you are cool with spending more time at it I would recommend getting this:

bookhttps://www.amazon.ca/Programming-Language-2nd-Brian-Kernighan/dp/0131103628

Everything is super clear and it should be everything you need to know, at least to start

How about this book?

C was my first programming language. I learned from multiple books and realized it was more about building programming skill. I would suggest this book for programming skill in C-

C In Depth

I asked an ICPC coach and he said 4 things:

1. This book from Felix and Steven Halim is pretty good.Here is an Amazon link, but you could order from other places and maybe save a bit.
2. Online contest sites like Kattis and CodeForces let you sort problems either by difficulty or by the number of people who solved them (Proxy for difficulty). You can try to move up their leaderboards.
3. ICPC itself publishes the contest problems and also videos of the solutions (done in English) on their YouTube if you want detailed workthroughs on how to approach some of the most difficult problems.
4. If you live near a university, you can just call their CS department and ask who their competitive programming coach is. If you ask, they might let you come to practices with their team (he said he would).

Best book is still https://www.amazon.com/Programming-Language-2nd-Brian-Kernighan/dp/0131103628

If you really want, you can find a free PDF of it. Just go through it pretty quickly, actually do the exercises so you get programming practice.

C++ is a superset of C, everything in C is in C++. You should learn C before C++. Once you know C, C++ comes a bit easier.

For learning C I can highly recommend The C Programming Language by Dennis Ritchie and Brian Kernighan, they wrote C so they're more than qualified to write a book on it and they do it well with examples and precision rather than information overload.

self-learner here,
"Introduction to Embedded Systems: Using ANSI C and the Arduino Development Environment" I don't know who much this book is relevant to what is your goal from learning C but it teaches C in first few chapters before the Arduino part.

C noob (coming from the web dev world) and I've only done it for personal enrichment, but A Book On C (ABC har har) was given to me years ago by a friend who has his PHD in Computer Science (or something like that) and he gave me the original printing from the 80s. When I sat down to learn C in earnest I got the updated one since the original was written before the ANSI C standard.

https://www.amazon.com/Book-Programming-4th-Al-Kelley/dp/0201183994/ref=sr_1_1?crid=2X3O4TRYFMMQR&keywords=a+book+on+c&qid=1647975352&sprefix=a+book+on+c%2Caps%2C88&sr=8-1

If my assumption is correct and you want to first solve the given polynom for user provided X and afterwards solve it for values from 0 to 5, I would probably solve it like this: https://repl.it/repls/ImaginaryDismalNonlinearprogramming

This way it is enough to define the polynom function only once and you don't even have to store the results if printing them out is the only thing you're after. Notice how my for loop is built in comparison to yours.

Also notice the difference in format specifying strings. Your code has %1f which I assume is incorrect and you really wanted to specify a double output. That should be %lf (lowercase letter L) instead. In your second formatting string you specify %ld which is a specifier for type long. Again, you're trying to output a double value, so it should be %lf instead.

Hope it helps :)

Code looks good to me.

Tried it with C/GCC (Windows Linux subsystem), works perfectly.

Tried it with C++/VS, works perfectly.

Tried it online, works perfectly.

Tried adding my own stack guards:

int start = 1351351351; char array123[4] = "123"; char array4[3] = "44"; char *stringp1 = array123; char *stringp2 = array4; int end = 1361361361;

They weren't changed at all.

I think there's something wrong on your end. Try removing your strcpy implementation and using the one in string.h instead.

An insertion sort inherently has specific traits.

> so theres no code to show or anything

If theres an implementation there is code. You might have to reverse the assembly, but its there. If were ONLY talking about theory, then see the wikipedia page.

I have a feeling you dont quite grasp what you are asking about. Perhaps a basic intro into BigO is in order? https://www.freecodecamp.org/news/big-o-notation-why-it-matters-and-why-it-doesnt-1674cfa8a23c/

Cmd+Space will bring up Spotlight, write "terminal" in there, and hit return/enter to open the Terminal application.

Using the Terminal on macOS is just the same as in any unix/linux system, as macOS is a Unix Compliant operational system. If you know how to use a Terminal in any Linux, you know how to use it on macOS...

If you don't know how, look for a book or tutorial about it.

Again, any book on "Linux Terminal" will do, but if you want for some reason a specific material, you'll find it as well.

Use the command 'cd' to change directories until you reach the code directory.

Once you enter the directory containing your code, you can use the 'gcc' command to compile the code.

Using ANY text editor alongside the Terminal is a common workflow, you can use Visual Code or whatever to edit your files, and use the Terminal to compile and run your code.

Treat macOS as any other "Linux" regarding on how to use the Terminal.

The Limux kernel coding style is pretty good.

Previously it read:

>Encoding the type of a function into the name (so-called Hungarian notation) is brain damaged - the compiler knows the types anyway and can check those, and it only confuses the programmer. No wonder MicroSoft makes buggy programs.

But they toned the language down a bit. It's now just asinine not Brain damaged and it doesn't reference MicroSoft anymore, probably because they shy away from it now too.

There are some cases where Hungarian notation is potentially useful, but Systems Hungarian (where you encode the type not some other semantic information) is never a good idea in a typed language.

I used this to get mingw-w64 installed and compiling. If you can get it to work with VS Code, you should be able to get it to work with VS Studio. Let me know how it goes.

https://codeshare.io/dwp3qD

Create a program that asks the user if he wants to see a square or cube number table

You want to see a square number table? choose option 1

You want to see a cube number table? choose option 2

Read options 1 and 2 (scanf) and use if where it shows

if opcao==1 -> show square number table

if opcao==2 -> show cubic number table

declared variables are a) option (opcao) and contador (counter)

Then finally thank the user for using the program (obrigado por usar o programa!)

I just wanna know if i'm doing this alright. Code is in the link

​

Thanks

https://www.hackerrank.com/ is a site where you can complete little challenges in certain domains. Its all online so need for a local development environment. Every domain has a nice learning curve and tasks have good descriptions. When you have solved a challenge your code will be tested extensively online whether you code really solves the problem along with all edge cases. There are also banges and a leader board.

Multiple languages are supported not only C.

I would suggest that you learn basic C (the syntax, memory management, pointers , functions, etc...) and then try Hackerrank (https://www.hackerrank.com/domains/c?badge_type=c) -

nnn supports several mechanisms to preview images in the terminal and ueberzug delivers the best results. However, technology keeps improving and I think libsixel is the most promising.

On Windows - SysInternals is the goto. Its a whole suite of tools but several will show you mapped in sections to what they are (range XXXX-XXXX is a stack, range YYYY-YYYY is a heap, range ZZZZ-ZZZZ is thisthing.dll) etc.

On Linux there are several tools, one of which is pmap.

Edit just used pmap on a process to see

00007fff3db27000 132K rw--- [ stack ]

So if i have a memory address in that range (00007fff3db27000 + 132K) its in the stack.

If all of the #include files are copied in by the preprocessor, wouldn't this result in the entire project reducing to one huge file to be compiled, producing only one object file?

This here for example, shows multiple object files being linked into one executable. https://www.hackerearth.com/practice/notes/what-happens-when-a-c-program-runs/

I love https://www.codewars.com for practicing new languages. They give you a small function to write, you write it in the language of your choice, and it gets run and tested on their servers. You can even work on writing your own problems for others to solve. You could select C as your preferred language and start working through beginner problems, and you would eventually work your way up to hard problems. I think that's great hands-on learning in addition to any reading.

This dub is for C programming. Try r/cpp. Also, algorithms and data structures are language agnostic. I found this among many others with a Google search, 8 Books on Algorithms and Data Structures For All Levels](https://www.tableau.com/learn/articles/books-about-data-structures-algorithms)

yea, Windows is pretty much useless unless you are at a school that is going to push you through multiple (4+) C#/WPF development classes.

Otherwise, Linux has MASSIVE advantages over Windows, so everything you create will be a *nix based OS. There might be something new that pops up in the next couple of years but RedHat is super duper strong. You should start learning about shared object files, ELF (Executable and Linkable Format), and just the general ecosystem. It is a rabbit hole so try to balance life and studying; however, if there is any time to explore Linux it's when you are an EE student in college. Also, never switch your major.

Read this before you graduate: https://www.amazon.com/Advanced-Programming-UNIX-Environment-3rd/dp/0321637739

If you want to be a hardcore coder, then take as many CS/CE classes that you can. If security interests you then double major in math, you will thank me later.

Write a gui program.

Weird, doesn't look like Kindle is on the phone but most likely this one.
Different people have different methods of learning, nowadays I do more hands-on approach. Having a hard time then create an app to better understand what the thing is doing.

My two favorite C books for covering the basics:

C by Example. Noel Kalicharan 978-0521450232

978-0393979503

This. If you are a complete beginner, the Learn C app from Programiz might be a good option.

Learn C Programming: Programiz - Apps on Google Play

Noob implementations, lack of optimization. For the first steps try: https://www.amazon.com/Data-Structures-Using-Yedidyah-Langsam/dp/0130369977

it is probably not what you are looking for, but there is an app on the playstore that is called "c4droid", and it allows you to write android apps driectly in C and it comes with a demo program that is called "cube", if i remember correctly..

https://play.google.com/store/apps/details?id=com.n0n3m4.droidc&hl=en_US

does that qualify as a game engine?

btw, it costs about three dollars, but it is really nice.. you can write a full android app directly on your phone.. better get a bluetooth keyboard..

/u/phao has a good question, and I don't have a great resource offhand, but 2 things...

Java, Python, PHP, Javascript, and (I assume at least) Ruby are all C like, so the syntax will look familiar enough that you could probably fake your way through a lot of it while searching online for details and function syntax. Picking up the K&R book might be enough to get you hacking away at work without much trouble.

In fact, you'll probably feel like you are picking things up really quickly (as far as C/C++ goes at least) and wonder why you were so worried in hindsight. There is one huge catch though and it cannot be emphasized how huge this catch is.

Java, Python, JS, PHP, and Ruby (I'm assuming on the last three, I haven't dealt with them much) don't have pointers. OK, yeah, Java has pointers all over the place ("references") but they are hidden from you. In C/C++ you can point a variable anywhere in memory that you want and read/write from it and it might just happen to work fine, until it doesn't, and those issues can be a huge pain to find. Plus, C/C++ doesn't have garbage collection so as you allocate memory and shift it around you are responsible to clean it up when you are done with it.

On paper it doesn't sound too bad, but this would be the area I feel like I see new people to the language have the most trouble with, especially coming from Java and scripted languages. Just be sure to pay extra attention in that section in the book.

K&R Book: http://www.amazon.com/dp/0131103628

Embedded.com has a decent reference: http://www.embedded.com/collections/4397931/Object-oriented-C

This book also has some good general OO design info in addition to the test info: http://www.amazon.com/Driven-Development-Embedded-Pragmatic-Programmers/dp/193435662X