【C语言】【unix c】编写代码实现基于UDP的网络通信

我就是我 2022-06-07 05:28 150阅读 0赞

编写代码实现基于UDP的网络通信：(userv.c uclie.c)
            userv.c:
                #include <stdio.h>
                #include <p_net.h>
                #include <ctype.h>
                int main(void) {
                    SA4 serv, cli;
                    int rcv;
                    char buf[128];
                    int cli_len = sizeof(cli);
                    //创建socket
                    int s_fd = socket(AF_INET, SOCK_DGRAM, 0);
                    if(s_fd == -1) {
                    perror("socket");
                    return -1;
                    }
                    //初始化服务器信息
                    serv.sin_family = AF_INET;
                    serv.sin_port = htons(7777);
                    serv.sin_addr.s_addr = htonl(INADDR_ANY);
    
                    int b = bind(s_fd, (SA*)&serv, sizeof(SA4));
                    if(b == -1) {
                    perror("bind");
                    return -1;
                    }
                    while(1) {
                    rcv = recvfrom(s_fd, buf, 128, 0, (SA*)&cli, &cli_len);
                    if(rcv > 0) {
                        int i;
                        for(i = 0; i < rcv; i++) {
                        buf[i] = toupper(buf[i]);
                        }
                        sendto(s_fd, buf, rcv, 0, (SA*)&cli, sizeof(SA4));
                    }
                    }
                    return 0;
                }
            uclie.c：
                #include <stdio.h>
                #include <p_net.h>
                #include <string.h>
    
                int main(int argc, char *argv[]) {
                    SA4 serv;
                    char *msg = "wang \n";
                    char *buf[128];
                    //创建socket
                    int s_fd = socket(AF_INET, SOCK_DGRAM, 0);
                    if(s_fd == -1) {
                    perror("socket");
                    return -1;
                    }
                    //初始化服务器的地址
                    serv.sin_family = AF_INET;
                    serv.sin_port = htons(7777);
                    inet_pton(AF_INET, argv[1], &serv.sin_addr);
                    //向服务器发消息
                    int s = sendto(s_fd, msg, strlen(msg), 0, (SA*)&serv,sizeof(SA4));
                    if(s == -1) {
                    perror("sendto");
                    return -1;
                    }
                    //等待从服务器段返回消息
                    int rcv = recvfrom(s_fd, buf, 128, 0, NULL, NULL);
                    write(1, buf, rcv);
                    close(s_fd);
                    return 0;
                }