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If a codebase has any of this stuff, you'll know it's been backdoored.

Aight I'm never listening to the word "pointer" again

"say pointer again" "fuck you"

You realize how complicated pointer syntax is when the best explanation of how to read complex statements is in a funny YT video

I honestly never had any issues understanding basic and more advanced pointer stuff, but THIS is some actual good stuff LMAO great video

Honestly, An array of functions sounds pretty dope. Nevermind, an array of pointers to functions sounds pretty dope.

Who the hell would write the last one, without questioning their lives decisions.

It all can get stupidly complicated as we've seen, but the syntax follows simple rules: 1. start reading from the identifier out 2. favor [ ] and ( ) over * int (*(*x)[ ]) ( ): - Following rule #1, we start at x x - The identifier x is alone in parentheses with an asterisk, so it is [§1] a pointer *x - Outside of the parentheses, we follow rule #2, so it is [§2] an array (*x)[ ] - We're left with an asterisk inside the parentheses, so [§3] pointers *(*x)[ ] - Outside of the parentheses, rule #2, [§4] functions (*(*x)[ ])( ) - The functions return [§5] int putting §1, §2, §3, §4 and §5 together: x is (§1) a pointer to (§2) an array of (§3) pointers to (§4) functions that return (§5) an integer Once you got the hang of it, you can rewrite the example like: * [ ] * ( ) -> int And stitch things together in a way that makes sense. "->" means "returns" and it's optional/redundant (anything immediately after parentheses in this notation is a return anyway) Take the example of 5:34: [ ] * * (* char, * (* char) -> * int) -> [ ] * (* * char, * ( ) -> * char) -> * int Array of pointers to a pointer to a function that takes (a pointer to a character and a pointer to a function that takes (a pointer to a character) and returns a pointer to an integer) and returns an array of pointers to a function that takes (a pointer to a pointer to a character and a pointer to a function that returns a pointer to a character) and returns a pointer to an integer It looks insane, but it's not that difficult to wrap your head around if you're writing it following those two simple rules

im actually glad i found this video, you explained this well and now i know how to interpret those long lines

to whoever reached a point in life where you ended up here or doing this, i really hope you find inner peace one day...

C's syntax makes things excessively hard to parse, in other languages like C3 or more Pascal style languages (like Go and Odin) it's much more clear how these declarations compose

I think, most of the confusion comes from the syntax. For example, int (*(*x)[])() in Rust, would be Box> "Box" is Rust's pointer i32 is Rust's int

"For example, if I use this struct 'Fucker'" caught me completely off guard XD My main takeaway from this video though is that as a C# dev for Unity, I shouldn't touch C++ with a 5 foot pole or else risk entering pointer hell.

bro lost me before the ad break 💀

I finally understood. The type signatures are provided not the obvious way around, but outside in. For example: int x() is a function named "x", returning an integer. But instead of "x", I can put something different and it will mean, put the whole function inside whatever is in that position. For example "int (*x)()" means to put the function inside the *x. So It's a pointer to a function. But it's not just functions, it's **everything** if we analyze the "int (*x)()" again we get: int , which means to put the integer inside something that something: () It's a function! which means, that we put our int iside the return paramater of that function what's something: * it's a pointer! which means, we put our whole function with integer return type into a pointer. that something: x It's a name "x" which means, we put our whole pointer to a function with a return type of integer into the name "x" Let's do another example: char *(*(*(**x[])())[])(); it's a char, which is in a pointer, which is in the return type of a function, which is in a pointer which is in an array which is in a pointer, which is in the return type of a function, which is in a pointer, which is in a pointer, which is in an array, which is in "x"

this is what I understood from 3:10 - arr[0] -> func1 => int1 - arr [1] -> func2 => int2 x ->arr - arr[2] -> func3 => int3 - arr[3] -> func4 => int4 - arr[4] -> func5 => int5

Man, It felt awesome and confusing at the same time, but thanks to you I come to know the different use of pointers.

6:00 Bro is holding the entire class inside his variable definition The God Variable.

0:14 as soon as i read "france" i subscribed and liked the video

Such an awesome teaching style!

That line of code in the thumbnail alone drove me insane and I haven't even watched the video yet.

I FINALLY GOT POINTERS after more than 15 tutorials and another 15 "explanation" videos, you somehow made my brain click. Thank you so much!

The fact that C lets you write stuff like this makes me think that someone forgot to write it as an entry in the Geneva convention

Entertaining and very educational for me. Seeing different uses of pointers that you tried to demonstrate and describe them made my me intrigue, but at the same time dizzy. 😂

"Go insane?" GO MENTIONED RAAAAAAAAAAAAAAAAAAAAAAAAA

In older computers, especially Lisp machines, pointers always came with a size. A pointer was a 2-D object to the hardware. It had a location, and a size. The weirdness of C/C++ pointer types is an attempt to recapture some of the elegance of earlier hardware in a later era where the hardware forgot about data safety.

what I get from this is that the song at the end rocks.

Ok how was this convoluted mess the thing that actually taught me how pointers work lol

This video made me cry

Actually the best explanation of these bullshit functions I’ve seen, thanks!

I think this video actually made these easier to parse.

My favorite programming channel

What i learned from this video is that function pointers are pretty cool! :)

ohhh, i get it, thx :D. Finally understand pointer in my 3rd year in uni :)

Understanding pointers, is like the Great Barrier between amateur devs and the pros! Because THIS is a concept in which knowing how computers actually works, helps tremendously!

A pointer consists of: 7, 9, 9, 9, 9, 9, 12. I.e. 7 bits unused, 12 bits for the physical offset in memory and the 9's are offsets into a page "tree" if you will . Most CPU's today only use four-level pages, so the top 16 bits (instead of 7) are unused - but Intel is starting to use five-level pages too. It's also why pages are 2^12 (4096) in size, and why large pages can be 2MB (2^(12+9)) and 1GB (2^(12+9+9)) respectively. You can cast a pointer to a number, and shift the bits into different values to clearly see how there's a clear pattern when you allocate memory etc.

Your memory view and c debugger in vscode look very nice. Could you do a video on how you set this up or just gimme some info lol im jealous.

Omg I never understood pointers so well as I do right now thanks to this video

Absolute heater 🔥🔥🔥🔥

awesome. dude I need your fonr and vscode thee right now

I understood 80% after 15 min totally

you shoud have mentioned operator precedence. and also thr syntax related to those concepts perfectly fit into english grammar. as a Türk, ı can say it in english (up to some point) but cannot think of its meaning because we build up the noun phrases other way around

I wish this was a joke of some kind, then I wouldn't want to cry

love the soundtrack

The way i look at it is, the way you declare a pointer, is the way you access it. So if you got int *(*p[]), you'd access the innermost value (being the int) in the same way: *(*p[i]). And then you work your way backwards To make the point(er) clearer ill go through this. So you access the int by doing *(*p[]), so *p[] is an array of pointers to int, and *p points to an array of pointers to int, and p is a pointer to an array of pointers to int

I seriously never could imagine insanity up to this level.

I like your vids a lot!

Hi, you have been found in my recommendation :O I'm watching it only 0:32 and already subscribed you. You have a funny sense of Humor btw xD.

I REFUSE to understand this syntax.

1. Love the suffering 2. Love the use of digimon story cyber sleuth ost, its suitable considering the BS that is the digivolution tree. 3. Great video

"getting into programming is easy" the programming in question:

also all this pointer magic can be neatly swept under the rug if you use a lot of typedefs with proper names, makes the code much easier to understand for everyone

A programmer goes to therapy. Therapist: Please tell me what you are scared of. Programmer: I am scared of pointers. Therapist: Okay, let me give you an array of pointers to handle them. Programmer: 😱😱😱

This makes me thankful for the C# syntax

I buried this nightmare 20 yrs ago. After watching I'm sure I'll get one tonight.

There's probably already been someone saying this, but at 1:09, the allocation for the FUCKER variable was technically not correct, since alignment could see the struct end up larger than the raw data it contains. For instance, if we used an int after the char[6], most compilers would add a 2-byte padding before it to ensure that the address of the int is divisible by 4 (size of a 32 bit int which I assume is what int is) In general, the safest option is to always use malloc(sizeof()); it'll give you the correct size the compiler will assign your structs

Ngl i actually understand now thanks 🥰😂

3:29 --> See line 15 (3:21) for further clarification. In short, line 25 is saying that you want to first dereference the pointer, followed by selecting the function at index 0 for that pointer; then you have to de-reference that index (the array itself decays to a pointer containing the addresses of each function) in order to call the function you want from that double pointer. i.e., createFunctionPointerArray() returns "& -> {&add, &subtract}". You're making an embedded function library, I guess you could say, that the variable references, and you have to dereference all those pointers to access the function you want. Easy to understand?

How to open that memory view in vs

A simple hack to read c types is to start from parenthesis and then read from right to left. So if you see something like int (*x)[4] its: *x - x is a pointer -------------------------^ [4] - to an array with length 4 -----------^ int - to an int ---------------------------^ Another example: int (*x)(char (*t)[4]) we start with parenthesis so x is a pointer then to the right we see another parenthesis so x it is a pointer to a function then we parse the arguments so the function takes a pointer t to an array of length 4 of chars an the original function x points to returns an int

Unirocanically very useful video. Mad respect at the dinosaurs who invented C lol

"Great, you've explained these quite well. Now use them."

somehow this made me understand pointers better than 4 years in uni

Is that the all-too-common array of arrays length 8 of pointers to functions returning pointer to array of pointers to char? (The order is name, sufix, prefix, and operators on a name before sufix brackets (i.e. function argumrents) infer that the function is what is being stored in that way, after that is what is being returned; this necessitates that the type before the sufix brackets be a pointer as anything else C wouldnt know how to store) (Also the question would not parse, let alone make sense, you declare an array of arrays of undefined length, thats not allowed, if it was itd be an array of arrays of pointer pointers to functions returning a pointer to arrays len 8 with pointers to int) Or, in simple terms, its probably a number. Tldr just use c++, rust, java, python, ets. C is for pointer tricks and programming elevators, not for actual use. Unless you're making an OS, then it may come of use. C walked so that higher level languages could run.

This video is amazing

I can't believe I actually was able to solve the last two after fumbling on all the previous ones (mainly because of parenthesis which changed if x was a pointer to an array or an array of pointers). I think I'm cursed now.

Pro Tip: Just add another */& or put around parentheses until you get no compilation errors.

On one hand, class/module structures and delegates are basically pointer stuff in pure C. In higher languages, these things 'look' much simpler, by simpler it means the context now spans several .cs files. :P On the other hand, your professor could give you a snippet of ASM code, and ask something like: provide an (or the most restrictive) equivalent C function signature of a CALL function in the code. Yes, you shall use "mov dh,word ptr [eax]" to figure out that eax is a pointer to the value dh now holds, and the only use case of the value being "test dh,dh" means eax can be a *byte, or *bool. :'D

You had me at "Fucker". Subscribed.

1:10 I'm pretty sure you can also use sizeof() directly instead of calculating manually

Please do a vid of how you got that view of memory!

Those complex function declarations make me think of complex relational database.

i like your funny words magic man

This actually made me understand pointer expressions. Thank you.

How did you not go insane sooner?!!?!?!???

Interfaces are a fine abstraction from function pointer madness

Ok i need revisit some pointer videos before understand this

Everytime I paused and I am shocked how i get it before you start telling how to understand it. Maybe because i have been doing reverse engineering and malware stuff for long time now. Those codes actually have hell of typecasting with different data types and sizes. But greater video !!! ❤

Even the parser gave up, and he's still going

I am subscribing without further questions

Bro what's your vs code theme it looks nice

I think that this is 100% the reason for the existence of the typedef keyword

Ive personally written terrible code like this and iirc it looked like this: #define FUNCORDER (int (* [])(struct data *)){func1, func2, func3} It is a staticly defined, "anonymous" array of function pointers that accept a pointer to a struct I made & return ints. All of this to save 1 switch statement

bro got every meme in his vault

yo! nice video! could i ask what mic do u use?

What font do you use ? that font is so cool !

I came into this, expecting to learn how to read that stuff. Sadly I don't think I learned anything (except maybe reading the decl from the inside outwards?). This video was entertaining though. Just to give you feedback

Hey man great video, but what is ypur extensions for memory looking and your theme

Now I'm seeing stars everywhere.

Your first example should fail to compile (if you use -Werror), because control reaches the end of non-void function; the curly braces shoulsn’t be there. Also, although it is useful to be able to read the types like this, the real way to handle them is to use `typedef`s to name the intermediate types. 3:20 You’re mixing up your types. This is probably C pre-23 so it works but not well. You should say as part of the type that the pointers in the array that two `int` arguments.

interviewer: Great, add it to our interview question list!

If I ever see a pointer to a pointer to a pointer or anything more nested than that, I'm deleting system32, quitting CS, and starting my career as a professional mind reader. Because taking a wild guess at whatever is going on inside someone's head would still be easier then desciphering some of this shit.

I have been working professionally with C for well over a decade. I know most of the ways it can bite. If I see any of these in production, I'm burning the codebase and walking away, and so should you.

what's the extension that u are using to see the memory ?

Incredible I still can't understand pointers yayyyy!!!

Can anyone tell me what theme is he using?

hey I just wondering how you have memory debugger in vscode? Reading those memory bars would greatly help me on pointers! Thanks

Here's a little tidbit for variable management, while GCC has it's cleanup attribute for a more generic solution that works without it (and a lot more flexibly too), here's my solution (copy pasting an entire header here): ```C #pragma once #include typedef unsigned long ulong; typedef unsigned int uint; typedef char const *str; typedef struct { size_t len; str txt; } strvec; #define bitsof(T) (sizeof(T) * CHAR_BIT) #define lengof(LIT) ((sizeof(LIT) / sizeof(LIT[0])) - 1) typedef struct expiry_link expire; typedef void (*expiryCB)( void *data ); struct expiry_link { void *data; expire *next, *prev; void (*expireCB)( void *ptr ); }; inline void expire_linked( expire *head ) { for ( expire *link = head->prev; link != head; link = link->prev ) link->expireCB( link->data ); } inline void expire_nothing( void *data ) { (void)data; } inline void insert_expirable( expire *head, expire *link ) { head->prev->next = link; link->prev = head->prev; head->prev = link; link->next = head; } inline void remove_expirable( expire *head, expire *link ) { link->prev->next = link->next; link->next->prev = link->prev; link->prev = NULL; link->next = NULL; } #define DECL_EXPIRY_HEAD() \ expire expiry_head = { NULL, &expiry_head, &expiry_head, expire_nothing } #define DECL_EXPIRABLE( NAME, FUNC ) \ expire expirable_##NAME = { (void*)&NAME, NULL, NULL, (expiryCB)FUNC } /* For libraries that have termination functions */ #define DECL_EXPIRYLIB( NAME, FUNC ) \ expire expirable_##NAME = { NULL, NULL, NULL, (expiryCB)FUNC } #define INSERT_EXPIRABLE(NAME) insert_expirable( &expiry_head, &expirable_##NAME ) #define REMOVE_EXPIRABLE(NAME) remove_expirable( &expiry_head, &expirable_##NAME ) #define EXPIRE_LINKED() expire_linked( &expiry_head ) #define EXTERN_EXPIRABLE_H_INLINES() \ extern inline void expire_linked( expire *head ); \ extern inline void expire_nothing( void *data ); \ extern inline void insert_expirable( expire *head, expire *link ); \ extern inline void remove_expirable( expire *head, expire *link ) ```

explaining GO pointers till i GO insane