我正在用C做一些基本的套接字编程,并且在尝试在其上运行代码的每台计算机上都遇到此错误。该代码可以很好地编译,但是当我尝试运行它时,出现错误setsockopt:协议(protocol)不可用。这似乎不是一个很常见的错误,但是我尝试在每台计算机上运行它时都遇到了这个错误。所有的计算机都是MacOS。

#include <unistd.h>
#include <stdio.h>
#include <sys/socket.h>
#include <stdlib.h>
#include <netinet/in.h>
#include <string.h>
#define PORT 8080
int main(int argc, char const *argv[])
{
    int server_fd, new_socket, valread;
    struct sockaddr_in address;
    int opt = 1;
    int addrlen = sizeof(address);
    char buffer[1024] = {0};
    char *hello = "Hello from server";

    // Creating socket file descriptor
    if ((server_fd = socket(AF_INET, SOCK_STREAM, 0)) == 0)
    {
        perror("socket failed");
        exit(EXIT_FAILURE);
    }

    // Forcefully attaching socket to the port 8080
    if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT,
                                                  &opt, sizeof(opt)))
    {
        perror("setsockopt");
        exit(EXIT_FAILURE);
    }
    address.sin_family = AF_INET;
    address.sin_addr.s_addr = INADDR_ANY;
    address.sin_port = htons( PORT );

    // Forcefully attaching socket to the port 8080
    if (bind(server_fd, (struct sockaddr *)&address,
                                 sizeof(address))<0)
    {
        perror("bind failed");
        exit(EXIT_FAILURE);
    }
    if (listen(server_fd, 3) < 0)
    {
        perror("listen");
        exit(EXIT_FAILURE);
    }
    if ((new_socket = accept(server_fd, (struct sockaddr *)&address,
                       (socklen_t*)&addrlen))<0)
    {
        perror("accept");
        exit(EXIT_FAILURE);
    }
    valread = read( new_socket , buffer, 1024);
    printf("%s\n",buffer );
    send(new_socket , hello , strlen(hello) , 0 );
    printf("Hello message sent\n");
    return 0;
}

有人告诉我,我需要包括setsockopt()方法,以便重新启动的进程可以连接到该地址而不会由于tcp连接关闭后的等待时间而被阻止。有人知道如何解决此错误吗?

最佳答案

我有一个类似的问题,只是替换这段代码

// Forcefully attaching socket to the port 8080
if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT, &opt, sizeof(opt)))

有了这个
// Forcefully attaching socket to the port 8080
if (setsockopt(server_fd, SOL_SOCKET, SO_REUSEADDR , &opt, sizeof(opt)))

这对我来说很好(在macOS上)。

关于c - 套接字编程-setsockopt : Protocol not available?,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/58599070/

10-09 09:01