server.c

我自己写的udp服务程序

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <sys/wait.h>
#include <time.h>
#include <stdio.h>
#include <stdlib.h>

#define MAXLINE 80
#define PORT 3490

struct control_data
{
    char motor_type;
    char motor_speed;
}contdata;


int server()
{
   int sockfd=-1;
   int clt_sockfd,n,stop,i=0;
   socklen_t len,slen;
   //int len;
   struct sockaddr_in servaddr,cliaddr;
   //char mesg[MAXLINE];

   n=-1;
   stop=-1;
   contdata.motor_type='0';
   contdata.motor_speed='0';


   sockfd=socket(AF_INET,SOCK_DGRAM,0);
   bzero(&servaddr, sizeof(servaddr));
   servaddr.sin_family = AF_INET;
   servaddr.sin_addr.s_addr = htonl(INADDR_ANY);
   servaddr.sin_port = htons(PORT);
   
   if(bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr))!=-1)
   {
        printf("Bind Success!\n");
        //exit(1);
   }
   while(1)
   {
        n=recvfrom(sockfd,&contdata,sizeof(struct control_data),0,(struct sockaddr*)&cliaddr,&len);

        if(n!=-1&contdata.motor_type!='0') 
        {
            printf("Recieved!\n");
            printf("%c,%c\n",contdata.motor_type,contdata.motor_speed);
            
        }     
        if(sendto(sockfd,&contdata,sizeof(struct control_data),0,(struct sockaddr*)&cliaddr,sizeof(struct sockaddr))!=-1)
        {
            printf("Send Success!\n");
            exit(1);
            
        }
                  
   }
   close(sockfd);
}