Detailed explanation of C language pointer: Say goodbye to confusion and easily understand memory addresses
Pointers are a core concept in C language and are also a point that many programmers are confused about. This article will explain the meaning of pointers in a simple and easy way, so that even beginners can easily understand.
House address analogy
We compare the pointer to the address of the house. Each house has a unique address, and the house itself represents the stored data (variables). We can find the house through the address, and likewise, the data stored in memory can be found through pointers.
Imagine you need to tell someone where your home is. You can describe your house (color, size, etc.), but this can lead to confusion as there may be many similar houses. But if you provide your address, it is accurate. A pointer is like this address, which points to the location of a specific data in memory.
Application of pointers
In C language, streets represent memory space, houses represent variables, and addresses are stored in pointers. Each variable has a unique memory address, just as every house has a unique address. This address is stored in the pointer variable.
Using pointers allows you to manipulate data more efficiently, just as providing accurate addresses is faster and more convenient than describing a house. This is one of the core reasons why C is efficient, as Linus Torvalds said:
C language can work efficiently with the operating system or machine.
C-language pointer syntax example
In the code:
-
*ptr
represents a pointer variable that stores the memory address of the variable. -
&var
gets the memory address of the variablevar
. -
*ptr
is like a note with an exact address written (&var
is the memory address itself). -
**ptr
is a pointer to a pointer, just like you need to put a note with the address written in somewhere and need to know where the note is. -
int
specifies that the data type of the variable pointed to by the pointer is an integer.
Summarize
While this is a simplified analogy, I hope it will help you understand the basic concepts of pointers. Pointers are the key to the efficiency of C language, and understanding pointers is crucial to mastering C language. It is worth mentioning that the C language is an important part of NASA's flight software.
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