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POSocket programming: recv/read issue
 

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    <p><strong>EDIT:</strong> the code below has been fixed to receive and send properly AND to account for the actual bytes of messages sent annd recieved (latter thanks to EJP)</p> <p>I'm programming with C in Unix.</p> <p>I have server and client that are supposed to exchange msgs. While client seems to send messages fine, server doesn't receive the messages the client is sending. I've tried using <code>recv()</code> and <code>read()</code> (i know they are practically the same thing but with extra flags on <code>recv()</code>) but I have no luck and I'm not really sure what the problem really is. </p> <p>I put <code>sleep(3)</code> in the client code after every time it sends a message but i see that once client and server are connected, server immediately closes without waiting for the incoming messages. What am i doing wrong?</p> <p>This is the client-side code:</p> <pre><code>#define SERVER_TCP_PORT 11112 #define MAX_DATA_SIZE 500 int main(int argc, char * argv[]) { int sockfd; char * host; char msg[MAX_DATA_SIZE];/* = "get my msg!\n";*/ int msg_len; struct hostent * hp; struct sockaddr_in client_address, server_address; printf("y halo thar\n"); // looking up from the host database if (argc == 2) host = argv[1]; else exit(1); printf("sdf\n"); hp = gethostbyname(host); if (!hp) exit(1); printf("host found\n"); // setting up address and port structure information bzero((char * ) &amp;server_address, sizeof(server_address)); // copy zeroes into string server_address.sin_family = AF_INET; bcopy(hp-&gt;h_addr, (char *) &amp;server_address.sin_addr, hp-&gt;h_length); server_address.sin_port = htons(SERVER_TCP_PORT); printf("set\n"); // opening up socket if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) &lt; 0 ) exit(1); printf("opened\n"); // connecting if (connect(sockfd, (struct sockaddr *) &amp;server_address, sizeof(server_address)) &lt; 0) exit(1); printf("connected\n"); int i; for (i = 0; i &lt; MAX_DATA_SIZE; ++i) { msg[i] = '.'; } msg[MAX_DATA_SIZE-1] = '\0'; for(i = 0; i &lt; 11; i++) { // send message to connected socket msg_len = write(sockfd, msg, MAX_DATA_SIZE); if(msg_len &lt; 1) printf("notsent\n"); else printf("%i bytes sent\n", msg_len); // recieve messages from connected socket msg_len = read(sockfd, msg, MAX_DATA_SIZE); if (msg_len &lt; 1) printf("not recieved\n"); else { printf("%i bytes received\n", msg_len); printf(msg); printf("\n"); } } // close connection close(sockfd); printf("closed\n"); } </code></pre> <p>and this is the server side</p> <pre><code>#define SERVER_TCP_PORT 11112 #define MAX_DATA_SIZE 500 int main() { printf("o halo thar\n"); int sockfd, new_sockfd; int client_addr_len; char msg [MAX_DATA_SIZE]; int msg_len; char got_msg [11] = "got ur msg\0"; struct sockaddr_in server_address, client_address; // setting up address and port structure information bzero((char * ) &amp;server_address, sizeof(server_address)); // copy zeroes into string server_address.sin_family = AF_INET; server_address.sin_addr.s_addr = htonl(INADDR_ANY); server_address.sin_port = htons(SERVER_TCP_PORT); // opening up socket if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) &lt; 0 ) exit(1); printf("socket is opened\n"); // binding if (bind(sockfd, (struct sockaddr *) &amp;server_address, sizeof(server_address)) &lt; 0) exit(1); printf("socket is bound\n"); // listening listen(sockfd,5); printf("listening\n"); // block and wait for an incoming connection client_addr_len = sizeof(client_address); new_sockfd = accept(sockfd, (struct sockaddr *) &amp;client_address, &amp;client_addr_len); if (new_sockfd &lt; 0) exit(1); printf("accepted\n"); int i; for( i = 0; i &lt; 11; i++) { // recieve messages from connected socket printf("waiting\n"); msg_len = read(new_sockfd, msg, MAX_DATA_SIZE); if (msg_len &lt; 1) { printf("no msg recieved\n"); } else { printf("bytes recieved: %i\n", msg_len); } // send message to connected socket msg_len = write(new_sockfd, got_msg, sizeof(got_msg)); if (msg_len &lt; 1) printf("not sent\n"); else printf("%i bytes sent\n", msg_len); } // close connection close(sockfd); printf("socket closed. BYE! \n"); } </code></pre>
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