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POTCP connection. How to make the client only send data at the moment of the server's read()?
 

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  1. POTCP connection. How to make the client only send data at the moment of the server's read()?
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    <p>I have a client in iPod iOS 4.3 and a server in Linux C. I can make a TCP connection and transfer data. </p> <p>The server runs in a cycle with read() and printf.The client should send data only when asked. I found out that even after one read(), printf and halting at a getchar(), the client (iPod) is still getting the messagem <em>NSStreamEventHasSpaceAvailable</em> and sends the data. </p> <p>After i press any key on the server, it gets to the read() again, and shows much more data. I just wanted some help about the synchronous/asynchronous and blocking/non-blocking setting i should use in both the client and server. (theoretical, thus no need for coding, i guess.)</p> <p>As requested, here is the server code:</p> <pre><code>void testApp::setup() { int portno; struct sockaddr_in serv_addr; socklen_t clilen; connection = 0; //Still no connection sockfd = socket(AF_INET, SOCK_STREAM, 0); if (sockfd &lt; 0) error("ERROR opening socket"); bzero((char *) &amp;serv_addr, sizeof(serv_addr)); portno = atoi("50000"); serv_addr.sin_family = AF_INET; serv_addr.sin_addr.s_addr = INADDR_ANY; serv_addr.sin_port = htons(portno); if (bind(sockfd, (struct sockaddr *) &amp;serv_addr,sizeof(serv_addr)) &lt; 0) error("ERROR on binding"); listen(sockfd,5); } void testApp::update() { int check = 0; int n; char buffer[256]; if(connection != 0) { check = recv(newsockfd, buffer, 256, MSG_PEEK|MSG_DONTWAIT); } /* developerweb.net/viewtopic.php?id=5627 */ if(connection == 0 /*1st connection*/ | check == 0 | (check &lt; 0 &amp;&amp; errno != EAGAIN)) { printf("CHECK é %d",check); if(connection != 0) { close(newsockfd); newsockfd = -1; printf("Client disconnected.\n");} printf("\n\n-=Waiting for connection...=-\n"); newsockfd = accept(sockfd,(struct sockaddr *) &amp;cli_addr,&amp;clilen); printf("\nClient connected successfuly! \n"); } if (newsockfd &lt; 0) {printf("ERROR on accept"); close(newsockfd); newsockfd=-1; } else if(newsockfd == 0) printf("No socket\n"); else { printf("Waiting for message...\n"); connection = 1; bzero(buffer,256); n = read(newsockfd,buffer,255); if (n &lt; 0) error("ERROR reading from socket"); printf("Here is the message: %s\n",buffer); } printf("\nPress any key to continue..."); getchar(); } </code></pre> <p>Thanks for any help.</p>
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    1. USStinkyCat
    1. USStinkyCat
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      1. VTUpMod
    1. COwhat does your server code look like?
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      1. USKiril
    2. COI will post it now.
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      1. USStinkyCat
 

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