linux实现udp

linux实现udp

前言：udp通信需指定自己的接收端口和IP地址，并且有至少两个线程，即发送和接收。

话不多说，看代码：

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <arpa/inet.h>
#include <pthread.h>

//发送信息线程
void *sendMsg(int to_port){
    //创建套接字
    int read_fd  = socket(AF_INET, SOCK_DGRAM, 0);
    if(read_fd == -1){
        perror("socket error");
        exit(1);
    }
    struct sockaddr_in to;
    memset(&to, 0, sizeof (to));
    to.sin_family = AF_INET;
    to.sin_port = htons(to_port);
    inet_pton(AF_INET, "127.0.0.1", &to.sin_addr.s_addr);
     printf("sendMsg:%d\n",to_port);
    while(1){
        //数据发送
        char buf[1024] = {0};
        fgets(buf, sizeof (buf), stdin);
        sendto(read_fd, buf, strlen(buf)+1, 0, (struct sockaddr*)&to, sizeof (to));
        printf("I say: %s\n", buf);
    }
    close(read_fd);
}
//接收信息线程
void *recieveMsg(int recieve_port){
    int write_fd  = socket(AF_INET, SOCK_DGRAM, 0);
    if(write_fd == -1){
        perror("socket error");
        exit(1);
    }
   printf("recieveMsg:%d\n",recieve_port);
   struct sockaddr_in I;
   memset(&I, 0, sizeof (I));
   I.sin_family = AF_INET;
   I.sin_port = htons(recieve_port);
   I.sin_addr.s_addr = htonl(INADDR_ANY);
   int ret = bind(write_fd, (struct sockaddr*)&I, sizeof (I));
   if(ret == -1){
       perror("bind error");
       exit(1);
   }
   char buf[1024] = {0};
   struct sockaddr_in client;
   socklen_t cli_len = sizeof (client);
   while(1){
       int recvlen = recvfrom(write_fd, buf, sizeof (buf), 0, (struct sockaddr*)&client, &cli_len);
       if(recvlen == -1){
          perror("recvfrom error");
          exit(1);
       }
       printf("he say: %s", buf);
   }
   close(write_fd);
}
int main(int argc, const char* argv[]){
    if(argc != 3){
        printf("Usage : ./client <recieve port> <sendto port>\n");
        return 0;
    }
     printf("recieve_port:%s++++++++to_port:%s\n",argv[1],argv[2]);
    pthread_t send_id, recieve_id;
    pthread_create(&send_id, NULL, sendMsg, atoi(argv[2]));
    pthread_create(&recieve_id, NULL, recieveMsg, atoi(argv[1]));
    pthread_join(send_id,NULL);
    pthread_join(recieve_id,NULL);
    return 0;
}

运行结果：

小白一个，还望各位大神指教。