Linux Socket编程简单实例

 

#include<stdio.h>#include<stdlib.h>#include<sys/types.h>#include<sys/socket.h>#include<netinet/in.h>#include<arpa/inet.h>#include<netdb.h>char *host_name="127.0.0.1";int port=7778;struct student{ char name[20]; char num[20]; float score;}t={"xiejian","200701415",89.9};int main ( ){ char buf[502]; int socket_descriptor; struct sockaddr_in pin; bzero(&pin,sizeof(pin)); pin.sin_family=AF_INET; inet_pton(AF_INET,host_name,&pin.sin_addr); pin.sin_port=htons(port); if((socket_descriptor=socket(AF_INET,SOCK_STREAM,0))==-1) {  perror("Error openung socket!/n");  exit(1); } if(connect(socket_descriptor,(void *)&pin,sizeof (pin))==-1) {  perror("can not connecting to server!/n");  exit (1); } printf("Send message  to server .../n"); //memset(buf,0,502); //memcpy(buf,(void *)&t,sizeof(t)); //sprintf(buf,"%s %d",t.name,t.num); //printf("the first string : %s/n",buf); if(send(socket_descriptor,(void *) &t,sizeof(t),0)==-1) {  perror("can not send message!/n");  exit (1); } printf("waiting for response from server!/n"); memset(buf,0,502); if(recv(socket_descriptor,buf,sizeof(buf),0)==-1) {  perror("can not receive response !/n");  exit (1); } printf("/n Response from server : /n"); memcpy((struct student *)&t,buf,sizeof(buf)); //printf("the string : %s /n",rebuf); printf("--%s--%s--%5.1f--/n",t.name,t.num,t.score); close (socket_descriptor);} /*  注意在send 结构体时应该把结构体强制类型转换为void * 型 **  接受之后又要强制转换回结构体型！否则则穿过来的是结构体的**  一部分！*/下面是服务端#include<stdio.h>#include<stdlib.h>#include<netinet/in.h>#include<sys/socket.h>#include<arpa/inet.h>#include<netdb.h>int port=7778;struct student{ char name[20]; char num[20]; float score;}t;main(){ struct sockaddr_in sin; struct sockaddr_in pin; int sock_descriptor; int temp_sock_descriptor; int size_of_addr; //struct cfg a; char buf[502]; int i,lenth; sock_descriptor=socket(AF_INET,SOCK_STREAM,0); if(sock_descriptor==-1) {   perror("socket!/n");  exit(1); } bzero(&sin,sizeof(sin)); sin.sin_addr.s_addr=INADDR_ANY; sin.sin_port=htons(port); if(bind(sock_descriptor,(struct sockaddr *)&sin,sizeof (sin))==-1) {  perror("bind!/n");  exit(1); } if(listen (sock_descriptor,20)==-1) {  perror("listen!/n");  exit(1); } printf("Waiting for accepting connection from client!/n"); while(1) {  printf("the process is waiting here!/n");  temp_sock_descriptor=accept(sock_descriptor, (struct sockaddr *)&pin,&size_of_addr);  if(temp_sock_descriptor==-1)  {   perror("call to accept!/n");   exit (1);  }  memset(buf,0,502);  if(recv(temp_sock_descriptor,buf,sizeof(buf),0)==-1)  {   perror("recv!/n");   exit (1);  }    printf("received : /n");  //printf("the recv buf is :%s/n",buf);  memcpy((struct student *) &t,buf,sizeof(buf));  printf("--%s--%s--%5.1f--/n",t.name,t.num,t.score);  if(send (temp_sock_descriptor,(void *) &t,sizeof(t),0)==-1)  {   perror("send!/n");   exit(1);  }  close (temp_sock_descriptor); }}