socket通信传送结构体！

socket通信可以直接传送结构体！

示例：

（发送端）

struct student{char name[20];int age;};struct student student1={"liuxiaobing",23};

接受端：

struct student{char name[20];int age;};struct student *student_client = NULL;while(1){n = read(sockfd, recvline, MAXLINE);if(n == -1){perror("read error");exit(1);}student_client = (struct student *)recvline;//recvline[n] = 0; printf("Receive：name=%s***age=%d/n",student_client->name,student_client->age);//fputs(recvline, stdout);//printf("%s/n",recvline);}

 

 

UDPsocket通信简单的代码：

udpserv.c

/*udpserv.c*/#include <sys/types.h>#include <sys/socket.h>#include <string.h>#include <netinet/in.h>#include <stdio.h>#include <stdlib.h>#include <stddef.h>#include <unistd.h>#include <pthread.h>#define MAXLINE 100#define SERV_PORT 8888int sockfd;struct sockaddr_in servaddr, cliaddr;socklen_t len;struct student{char name[20];int age;};struct student student1={"liuxiaobing",23};void get_msg(){int n;//socklen_t len;char mesg[MAXLINE];while(1){memset(mesg,0,MAXLINE);len = sizeof(cliaddr)+1;// waiting for receive data n = recvfrom(sockfd, mesg, MAXLINE, 0, (struct sockaddr *)&cliaddr, &len);printf("对方：%s/n",mesg);//printf("n = %d/n",n);// sent data back to client //sendto(sockfd, mesg, n, 0, (struct sockaddr *)&cliaddr, len);}}void send_msg(){int n;char sendline[MAXLINE];//while(fgets(sendline, MAXLINE, stdin) != NULL)while(1){//printf("%s/n",sendline);n = strlen(sendline);//printf("n=%d/n",n);sendto(sockfd, (void *)&student1, sizeof(student1), 0, (struct sockaddr *)&cliaddr, len);sleep(1);} }int main(void){pthread_t threadin,threadout;void *retval;printf("%s/n%d/n",student1.name,student1.age);sockfd = socket(AF_INET, SOCK_DGRAM, 0); /* create a socket *//* init servaddr */bzero(&servaddr, sizeof(servaddr));servaddr.sin_family = AF_INET;servaddr.sin_addr.s_addr = htonl(INADDR_ANY);servaddr.sin_port = htons(SERV_PORT);/* bind address and port to socket */if(bind(sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr)) == -1){perror("bind error");exit(1);}//do_echo(sockfd, (struct sockaddr *)&cliaddr, sizeof(cliaddr));pthread_create(&threadin,NULL,(void *)(&get_msg),NULL);pthread_create(&threadout,NULL,(void *)(&send_msg),NULL);pthread_join(threadin,&retval);pthread_join(threadout,&retval);return 0;} 

udpclient.c

#include <sys/types.h>#include <sys/socket.h>#include <string.h>#include <netinet/in.h>#include <stdio.h>#include <stdlib.h>#include <arpa/inet.h>#include <stddef.h>#include <unistd.h>#include <pthread.h>#define MAXLINE 80#define SERV_PORT 8888int sockfd;struct sockaddr_in servaddr;struct student{char name[20];int age;};void get_msg(){int n;char sendline[MAXLINE], recvline[MAXLINE + 1];struct student *student_client = NULL;socklen_t servlen;servlen = sizeof(servaddr)+1;if(connect(sockfd, (struct sockaddr *)&servaddr, servlen) == -1){perror("connect error");exit(1);}while(1){n = read(sockfd, recvline, MAXLINE);if(n == -1){perror("read error");exit(1);}student_client = (struct student *)recvline;//recvline[n] = 0; printf("Receive：name=%s***age=%d/n",student_client->name,student_client->age);//fputs(recvline, stdout);//printf("%s/n",recvline);}}void send_msg(){char sendline[MAXLINE];while(fgets(sendline, MAXLINE, stdin) != NULL){write(sockfd, sendline, strlen(sendline));}}int main(int argc, char **argv){pthread_t threadin,threadout;void *retval;/* check args */if(argc != 2){printf("usage: udpclient <IPaddress>/n");exit(1);}/* init servaddr */bzero(&servaddr, sizeof(servaddr));servaddr.sin_family = AF_INET;servaddr.sin_port = htons(SERV_PORT);/*用inet_pton判断输入的ip（存在argv[1]中）是否合法,并转化格式*/if(inet_pton(AF_INET, argv[1], &servaddr.sin_addr) <= 0){printf("[%s] is not a valid IPaddress/n", argv[1]);exit(1);}sockfd = socket(AF_INET, SOCK_DGRAM, 0);/*create a socket*///do_cli(stdin, sockfd, (struct sockaddr *)&servaddr, sizeof(servaddr));pthread_create(&threadin,NULL,(void *)(&get_msg),NULL);pthread_create(&threadout,NULL,(void *)(&send_msg),NULL);pthread_join(threadin,&retval);pthread_join(threadout,&retval);return 0;}

 

分别编译：

gcc -l pthread -o udpserv udpserv.c

gcc -l pthread -o udpclient udpclient.c

 

服务端（ip：10.10.19.225）运行：

#./udpserv

客户端运行：

#./udpclient 10.10.19.225

hello（输入hello回车）

观察两端效果.

由于UDP是不可靠的，非连接通信，所以要先从客户端发消息。