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Thread: Winsock API - send an receive data simultaneously

  1. #1

    Default Winsock API - send an receive data simultaneously

    I'm trying to build a client and a server in the same program. For example, user 1 sends a packet of data to user 2, user 2 after receiving the packet sends back a different packet to user 1. The problem is, after running the program neither user receives the packets.


    Qt Code:
    1. #pragma comment(lib,"ws2_32.lib")
    2. #include <WinSock2.h>
    3. #include <iostream>
    4.  
    5. static char buffer[8096 + 1];
    6. char a[256] = {};
    7. char MOTD[256];
    8.  
    9. int main()
    10. {
    11. //WinSock Startup
    12. WSAData wsaData;
    13. WORD DllVersion = MAKEWORD(2, 1);
    14. if (WSAStartup(DllVersion, &wsaData) != 0) //If WSAStartup returns anything other than 0, then that means an error has occured in the WinSock Startup.
    15. {
    16. MessageBoxA(NULL, "WinSock startup failed", "Error", MB_OK | MB_ICONERROR);
    17. return 0;
    18. }
    19.  
    20.  
    21.  
    22. SOCKADDR_IN addr; //Address that we will bind our listening socket to
    23. int addrlen = sizeof(addr); //length of the address (required for accept call)
    24. addr.sin_addr.s_addr = inet_addr(INADDR_ANY); //Broadcast locally
    25. addr.sin_port = htons(1111); //Port
    26. addr.sin_family = AF_INET; //IPv4 Socket
    27.  
    28.  
    29.  
    30.  
    31.  
    32. SOCKET sListen = socket(AF_INET, SOCK_STREAM, NULL); //Create socket to listen for new connections
    33. bind(sListen, (SOCKADDR*)&addr, sizeof(addr)); //Bind the address to the socket
    34. listen(sListen, SOMAXCONN); //Places sListen socket in a state in which it is listening for an incoming connection. Note:SOMAXCONN = Socket Oustanding Max Connections
    35.  
    36. SOCKET newConnection;
    37. newConnection = accept(sListen, (SOCKADDR*)&addr, &addrlen);
    38. if (newConnection == 0){
    39. std::cout << "Failed to accept the client's connection." << std::endl;
    40. }else{
    41. std::cout << "Client Connected!" << std::endl;
    42. }
    43.  
    44.  
    45.  
    46. for( int i=0;i< 10;i++ ){
    47. if (connect(newConnection, (SOCKADDR*)&addr, sizeof(addr)) != 0) //If we are unable to connect...
    48. {
    49. MessageBoxA(NULL, "Failed to Connect", "Error", MB_OK | MB_ICONERROR);
    50. std::cout << WSAGetLastError();
    51.  
    52. }else{
    53. std::cout << 123;
    54. }
    55. }
    56.  
    57.  
    58.  
    59. while (true){
    60.  
    61. std::cin >> a;
    62. send(newConnection, a, sizeof(a), NULL);
    63.  
    64.  
    65. recv(newConnection, MOTD, sizeof(MOTD), NULL);
    66. std::cout << "MOTD:" << MOTD << std::endl;
    67. }
    68.  
    69. system("pause");
    70. return 0;
    71. }
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  2. #2
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    Default Re: Winsock API - send an receive data simultaneously

    you while loop is only tending to the newConnection socket.
    the sListen socket gets no CPU time.
    ==========================signature=============== ==================
    S.O.L.I.D principles (use them!):
    https://en.wikipedia.org/wiki/SOLID_...iented_design)

    Do you write clean code? - if you are TDD'ing then maybe, if not, your not writing clean code.

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