Five common Go language interview questions and answers

As a programming language that has become very popular in recent years, Go language has become a hot spot for interviews in many companies and enterprises. For beginners of the Go language, how to answer relevant questions during the interview process is a question worth exploring. Here are five common Go language interview questions and answers for beginners’ reference.

1. Please introduce how the garbage collection mechanism of Go language works?

The garbage collection mechanism of Go language is based on the mark-sweep algorithm and the three-color marking algorithm. When the memory space in the Go program is not enough, the Go garbage collector scans all pointers to objects in the memory area and marks the referenced objects. Afterwards, the program will clear the memory area of ​​all unmarked objects, thereby freeing the memory.

In the garbage collection mechanism of the Go language, the scanning and cleaning operations of the garbage collector usually occur in the background and are automatically completed by the Go language runtime system. Therefore, developers do not need to manually implement garbage collection mechanisms.

2. Please explain what goroutine is in Go language?

Goroutine is a lightweight thread implementation in the Go language. It uses pipe and channel technology to support multi-threaded concurrent operations. In the Go language, each goroutine has an independent stack space and function call stack, and can run multiple goroutines simultaneously in a Go program.

Compared with traditional threads, goroutine has the following advantages:

• Using goroutine can avoid resource waste when threads wait;
• goroutine can use the CPU more efficiently Resources;
• goroutine can achieve concurrency at the code level, simplifying program implementation difficulty and maintenance costs.

Due to the lightweight nature of goroutine, thousands of goroutines can be run simultaneously in the Go language, supporting high-concurrency application development.

3. Please introduce what is channel in Go language?

Channel is an important mechanism in the Go language for goroutine communication and synchronization operations. It is similar to the pipe in the Unix system and allows different goroutines to send and receive data to each other.

When using a channel, you first need to create a channel object, and then you can use the goroutine communication operator "<-" to send or receive data to the channel. By using channels, you can avoid multiple goroutines competing for a shared memory area, thereby avoiding concurrency issues other than locks, and also effectively reducing the occurrence of deadlocks.

4. Excuse me, how are pointers used in Go language?

In the Go language, a pointer is a data type used to directly access memory addresses. Unlike other programming languages ​​such as C/C, pointers in the Go language cannot perform pointer arithmetic, obtain the address of the pointer itself, or convert the pointer to an integer type.

When using pointers, you need to declare a pointer variable first and use the & operator to obtain the address of the variable. Afterwards, the value of the variable can be accessed using the * operator. For example:

var x int = 10
var ptr *int     //声明一个int类型的指针变量ptr
ptr = &x         //将x的地址赋值给ptr
fmt.Printf("x的值为%d
", *ptr)

It should be noted that in most cases, pointers can be used in Go language to make function calls instead of passing values, thereby reducing the cost of memory copying.

5. Excuse me, what is the function of defer statement in Go language?

The defer statement is a grammatical structure in the Go language, which is used to delay the execution of a function call when the function exits. In the Go language, the defer statement is usually used to release some resources, such as file closing, database connection closing, etc.

It should be noted that the order of execution of defer statements is last-in-first-out (LIFO), that is to say, the defer statement that is delayed called first will be executed last.

The above are only five common Go language interview questions and answers. The Go language itself has rich features and grammar, and the various questions during the interview process also vary from person to person. But in general, through in-depth understanding and practice of the Go language, as well as sufficient preparation before the interview, you will be able to demonstrate good programming literacy and strength during the interview process.

The above is the detailed content of Five common Go language interview questions and answers. For more information, please follow other related articles on the PHP Chinese website!