这一对C/S程序有问题么？

huyongzs

这段程序的问题是客户端能收到并输出服务端的的返回信息字符串。但是服务端能收到却不能显示客户端发来的字符串.

server端是过去装的debian stable
client端是新装的ebian testing

1. #include <stdio.h>
   
2. #include <sys/socket.h>
   
3. #include <netinet/in.h>
   
4. #include <arpa/inet.h>
   
5. #include <netdb.h>
   
6. 
   
7. int port =8000;
   
8. 
   
9. void main(){
   
10. struct sockaddr_in sin;
    
11. struct sockaddr_in pin;
    
12. int sock_descriptor;
    
13. int temp_sock_descriptor;
    
14. int address_size;
    
15. char buf[16384];
    
16. int i,len;
    
17. 
    
18. sock_descriptor = socket(AF_INET,SOCK_STREAM,0);
    
19. if(sock_descriptor == -1){
    
20.    perror("call to socket");
    
21. }
    
22. bzero(&sin,sizeof(sin));
    
23. sin.sin_family = AF_INET;
    
24. sin.sin_addr.s_addr = INADDR_ANY;
    
25. sin.sin_port = htons(port);
    
26. 
    
27. if(bind(sock_descriptor,(struct sockaddr *)&sin,sizeof(sin)) == -1){
    
28.   perror("call to bind");
    
29.   exit(1);
    
30. }
    
31. if (listen(sock_descriptor,20) == -1){
    
32.    perror("call to listen");
    
33.    exit(1);
    
34. }
    
35. printf("Accepting connection ...\n");
    
36. 
    
37. while(1){
    
38. temp_sock_descriptor = accept(sock_descriptor, (struct sockaddr *)&pin,&address_size);
    
39. 
    
40. if(temp_sock_descriptor == -1){
    
41.   perror("call to accept");
    
42.   exit(1);
    
43. }
    
44. if(recv(temp_sock_descriptor,buf,16384,0) == -1){
    
45.   perror("call to recv");
    
46.   exit(1);
    
47. }
    
48. printf("received from client:%s\n",buf);
    
49. 
    
50. 
    
51. len = strlen("OK.OK.OK.OK!");
    
52. 
    
53. if(send(temp_sock_descriptor,"OK,OK,OK,OK!",len,0) == -1){
    
54.   perror("call to send");
    
55.   exit(1);
    
56. }
    
57. close(temp_sock_descriptor);
    
58. }
    
59. }
    

复制代码

client:

1. #include <stdio.h>
   
2. #include <sys/socket.h>
   
3. #include <netinet/in.h>
   
4. #include <arpa/inet.h>
   
5. #include <netdb.h>
   
6. 
   
7. char *host_name = "192.168.0.101";
   
8. int port = 8000;
   
9. 
   
10. void main(int argc,char *argv[]){
    
11.      char buf[8192];
    
12.      char message[256];
    
13.      int socket_descriptor;
    
14.      struct sockaddr_in pin;
    
15.      struct hostent *server_host_name;
    
16. 
    
17. char *str = "A default test string";
    
18. 
    
19. if(argc < 2){
    
20.   printf("Usage:'clinet "Any test string"\n");
    
21.   printf("We will send a default test string.\n");
    
22. } else{
    
23. str=argv[1];
    
24. }
    
25. if((server_host_name = gethostbyname(host_name)) ==0){
    
26.   perror("Error resolving local host\n");
    
27.   exit(1);
    
28. }
    
29. bzero(&pin,sizeof(pin));
    
30. pin.sin_family = AF_INET;
    
31. pin.sin_addr.s_addr = htonl(INADDR_ANY);
    
32. pin.sin_addr.s_addr = ((struct in_addr *) (server_host_name->h_addr))->s_addr;
    
33. pin.sin_port = htons(port);
    
34. 
    
35. if((socket_descriptor = socket(AF_INET,SOCK_STREAM,0)) == -1){
    
36.   perror("Error opening socket\n");
    
37.   exit(1);
    
38. }
    
39. if(connect(socket_descriptor,(void *)&pin,sizeof(pin)) == -1){
    
40.   perror("Error connecting to socket\n");
    
41.   exit(1);
    
42. }
    
43. printf("Sending message %s to server...\n",str);
    
44. 
    
45. if(send(socket_descriptor,buf,8192,0) == -1){
    
46.   perror("Error in send\n");
    
47.   exit(1);
    
48. }
    
49. printf("..sent message.. wait for response..\n");
    
50. 
    
51. if(recv(socket_descriptor,buf,8192,0) == -1){
    
52.   perror("Error in receiving response from server\n");
    
53.   exit(1);
    
54. }
    
55. printf("\n Response from server:\n\n%s\n",buf);
    
56. close(socket_descriptor);
    
57. }
    
58. 
    

复制代码

Arthur.Echo

服务器端接收的数据没有NULL结尾
if(recv(temp_sock_descriptor,buf,16384,0) == -1){
  perror("call to recv");
  exit(1);
}
printf("received from client:%s\n",buf);
你用printf("%s",buf)当然打印会出问题的，改成这样的试试：
int bytes;
if((bytes = recv(temp_sock_descriptor,buf,16383,0) ) < 0){
  perror("call to recv");
  exit(1);
}
buf[bytes] = '\0';
printf("received from client:%s\n",buf);

Arthur.Echo

你的客户端程序的
if(send(socket_descriptor,buf,8192,0) == -1){
  perror("Error in send\n");
  exit(1);
}
中的buf好像什么东西都没有哦！！而且还有很多没有用的东西