golang套接字的实现_Golang

在 go 语言中，使用标准库 net 来实现套接字编程。以下是有关 go 套接字的基本概念和示例。

1. 基本概念

网络类型：
- tcp：流套接字，提供可靠的、面向连接的通信。
- udp：数据报套接字，无连接，适用于快速传输。

2. tcp 套接字示例

服务器端代码

package main

import (
    "fmt"
    "net"
)

func main() {
    // 创建 tcp 套接字
    listener, err := net.listen("tcp", ":12345")
    if err != nil {
        fmt.println("error starting server:", err)
        return
    }
    defer listener.close()

    fmt.println("waiting for a connection...")
    for {
        // 接受连接
        conn, err := listener.accept()
        if err != nil {
            fmt.println("error accepting connection:", err)
            continue
        }
        fmt.println("connection established from", conn.remoteaddr())

        // 处理连接
        go handleconnection(conn)
    }
}

func handleconnection(conn net.conn) {
    defer conn.close()
    message := "hello, client!"
    conn.write([]byte(message))
    fmt.println("message sent to client:", message)
}

客户端代码

package main

import (
    "fmt"
    "net"
)

func main() {
    // 连接到服务器
    conn, err := net.dial("tcp", "localhost:12345")
    if err != nil {
        fmt.println("error connecting to server:", err)
        return
    }
    defer conn.close()

    // 接收数据
    buffer := make([]byte, 1024)
    n, err := conn.read(buffer)
    if err != nil {
        fmt.println("error reading from server:", err)
        return
    }

    fmt.println("received message from server:", string(buffer[:n]))
}

3. udp 套接字示例

服务器端代码

package main

import (
    "fmt"
    "net"
)

func main() {
    // 创建 udp 套接字
    address, err := net.resolveudpaddr("udp", ":12345")
    if err != nil {
        fmt.println("error resolving address:", err)
        return
    }

    conn, err := net.listenudp("udp", address)
    if err != nil {
        fmt.println("error listening:", err)
        return
    }
    defer conn.close()

    fmt.println("waiting for a connection...")
    for {
        buffer := make([]byte, 1024)
        n, addr, err := conn.readfromudp(buffer)
        if err != nil {
            fmt.println("error reading from udp:", err)
            continue
        }
        fmt.println("received message from", addr, ":", string(buffer[:n]))

        // 发送响应
        response := []byte("hello, udp client!")
        conn.writetoudp(response, addr)
    }
}

客户端代码

package main

import (
    "fmt"
    "net"
)

func main() {
    // 发送 udp 数据包
    address, err := net.resolveudpaddr("udp", "localhost:12345")
    if err != nil {
        fmt.println("error resolving address:", err)
        return
    }

    conn, err := net.dialudp("udp", nil, address)
    if err != nil {
        fmt.println("error connecting:", err)
        return
    }
    defer conn.close()

    message := []byte("hello, server!")
    conn.write(message)

    // 接收响应
    buffer := make([]byte, 1024)
    n, _, err := conn.readfromudp(buffer)
    if err != nil {
        fmt.println("error reading from server:", err)
        return
    }

    fmt.println("received message from server:", string(buffer[:n]))
}