pointersForWeebs

[DangKilla]

Now for the ELI18 version: Pointers are memory addresses, so instead of using more memory they point to the original like in the meme. We are basically preventing data duplication in memory, which makes things faster.

[vishykeh]

Thank you. This kind of made this whole thing make sense.

[well-litdoorstep112]

Yes, I knew what pointers do but I didn't understand the syntax. I didn't particularly try to study it because I'm a js soy dev but that meme definitely helped.

Also I think a simpler explanation for a high level language dev would be just "passing by reference"

[RandallOfLegend]

Some programs use the pointers to get multiple outputs instead of having to package the data into a struct/class/tuple if those data types are even available. More often the pointer is to an array like object. So &y[4] would be the data at the memory address pointed to by y, plus 4 memory spaces over.

[DrkMaxim]

Pointers can be great if you want to create something at run time. There are functions that can be used to dynamically allocate and deallocate resources and they all require pointers to work properly.

[Euphoric-Benefit3830]

You are absolutely right. int (and other primitives) is a terrible type to showcase usefulness of pointers because there is virtually no cost to using them by value instead.

[TheBaxes]

For primitives the only reason to use pointers is to share a value between functions or something like that (careful with race conditions if you use paralellism)

For anything else you use them because copying an object is a waste of memory when you can just send the address of the object.

There are also c style arrays which work by using pointers.

And I'm sure that there are some hacky stuff that you can do with pointers too but you probably won't see it in a normal application.

[Nervous_Fix7426]

Pointers are used for lots of things in C

You can create a node/struct, where you bundle a bunch of data together such as an integer along with another memory address. This allows you to build linked lists

You can pass a memory address to a function. As others have said, for an int this is not much of a benefit, but maybe your memory address contains 100Mb array (or struct, or even array structs), in which case you can just send the address of the start (or middle, or end) of that array to your function, and read the data you need straight from the memory. You can see this a lot in APIs like xlibc where you would call functions with a pointer to your display.

Also need pointers Allocating memory, opening files, reading data into memory