Move pointer in arrays with C

Question

Is there anyway I can move the pointer in the array. So, like you move where the pointer is pointing at in the array. For files, I know that you can use fseek with something like fread to only copy from a specific location.

I'm trying to copy parts of an array into different files. With fwrite, it doesn't give the option to start from a specific location, so I'll need to move the pointer to somewhere in the array, then copy a part of the array into a file.

Answer 1

sure you can move a pointer. Say we have an array of ints

int arr[50];

set p to point at the first element

int*p = &arr[0];

now move it along by 10

p += 10;

p now points at arr[10];

Addition on a pointer is defined as incrementing the pointer by n times the size of each elements. Subtraction works too. Be aware of going off either end though, C wont look out for you. Ie this

p += 500;

will compile but will lead to undefined behavior if you try to use p;