Let's summarize the pointers of C language (basic edition)

I recently found out that pointers are also used in Go language, so I'm not sure if it can be applied. Let's summarize the pointers in C language that I used before.

What is a pointer in the first place?

A variable that stores the memory address of the variable. Variables and functions are stored in memory, and variables that have information indicating where they are located are pointer variables.

○ Example: Relationship between address and value when a variable is declared

/*Variable declaration*/
int A;
/*Declaration of pointer variables*/
int* pA;
/*Assign a value to a variable*/
A = 10;
/*Store the address of A in the pointer*/
pA = &A;

With the above contents, the value is stored in the memory in the following form. In the case of the above figure, '10' is stored in `0xXXXX4 ~ 0xXXXX7``` when the value is stored in the variable (the fact that multiple addresses are secured here will be explained later. ) In the example, the address of'''A''' is assigned to the pointer variable'''pA''', so `0xXXXX4``` is entered in'''pA'''.

• By the way, 4 addresses are reserved because the int type size is 4 bytes. The type size of variables is a way to remember pointers, so I will explain it in detail in the following article (Notes).

Basic usage of pointers

You can check the address of the memory by using the pointer, and you can also operate the value of the address.

○ Each operation method of the pointer

/*Get the address of a variable*/
/* &You can get the address of the target variable by adding to the beginning of the variable.*/
/*In the following cases, assign the address to the pointer variable pA*/
pA = &A;
/*Pointer destination(Address destination)To access*/
/* *You can access the address stored in the variable by adding to the beginning of the variable.*/
/*In the following cases, the value of the address destination stored in the pointer variable pA is rewritten to 20.*/
*pA = 20;

The figure below shows the above. This is the basis of pointers. From here, I would like to continue as an article such as points to note about pointers and advanced editions.