Databases
StackOverflow2013
Postsdbo
PODo I have to bind a UDP socket in my client program to receive data? (I always get WSAEINVAL)
 

Note that there are some explanatory texts on larger screens.

plurals
  1. PODo I have to bind a UDP socket in my client program to receive data? (I always get WSAEINVAL)
    primarykey
    data
    text
    <p>I am creating a UDP socket (<code>AF_INET</code>, <code>SOCK_DGRAM</code>, <code>IPPROTO_UDP</code>) via Winsock and trying to <code>recvfrom</code> on this socket, but it always returns -1 and I get WSAEINVAL (10022). Why?</p> <p>When I <code>bind()</code> the port, that does not happen, but I have read that it is very lame to bind the client's socket.</p> <p>I am sending data to my server, which answers, or at least, tries to.</p> <pre><code>Inc::STATS CConnection::_RecvData(sockaddr* addr, std::string &amp;strData) { int ret; // return code int len; // length of the data int fromlen; // sizeof(sockaddr) char *buffer; // will hold the data char c; //recv length of the message fromlen = sizeof(sockaddr); ret = recvfrom(m_InSock, &amp;c, 1, 0, addr, &amp;fromlen); if(ret != 1) { #ifdef __MYDEBUG__ std::stringstream ss; ss &lt;&lt; WSAGetLastError(); MessageBox(NULL, ss.str().c_str(), "", MB_ICONERROR | MB_OK); #endif return Inc::ERECV; } ... </code></pre> <p>This is a working example I wrote a few moments ago, and it works without the call to <code>bind()</code> in the client:</p> <pre><code>#pragma comment(lib, "Ws2_32.lib") #define WIN32_LEAN_AND_MEAN #include &lt;WS2tcpip.h&gt; #include &lt;Windows.h&gt; #include &lt;iostream&gt; using namespace std; int main() { SOCKET sock; addrinfo* pAddr; addrinfo hints; sockaddr sAddr; int fromlen; const char czPort[] = "12345"; const char czAddy[] = "some ip"; WSADATA wsa; unsigned short usWSAVersion = MAKEWORD(2,2); char Buffer[22] = "TESTTESTTESTTESTTEST5"; int ret; //Start WSA WSAStartup(usWSAVersion, &amp;wsa); //Create Socket sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP); //Resolve host address memset(&amp;hints, 0, sizeof(hints)); hints.ai_family = AF_INET; hints.ai_protocol = IPPROTO_UDP; hints.ai_socktype = SOCK_DGRAM; if(getaddrinfo(czAddy, czPort, &amp;hints, &amp;pAddr)) { std::cerr &lt;&lt; "Could not resolve address...\n"; std::cin.get(); return 1; } //Start Transmission while(1) { ret = sendto(sock, Buffer, sizeof(Buffer), 0, pAddr-&gt;ai_addr, pAddr-&gt;ai_addrlen); if(ret != sizeof(Buffer)) { std::cerr &lt;&lt; "Could not send data\n"; std::cin.get(); return 1; } fromlen = sizeof(SOCKADDR); ret = recvfrom(sock, Buffer, sizeof(Buffer), 0, &amp;sAddr, &amp;fromlen); if(ret != sizeof(Buffer)) { std::cout &lt;&lt; "Could not receive data - error: " &lt;&lt; WSAGetLastError() &lt;&lt; std::endl; std::cin.get(); return 1; } Buffer[ret-1] = '\0'; std::cout &lt;&lt; "Received: " &lt;&lt; Buffer &lt;&lt; std::endl; } return 0; } </code></pre>
    singulars
    1. PO
      singulars
      1. PTAnswer
    1. This table or related slice is empty.
    1. PTQuestion
    1. USWarren Young
    1. USIncubbus
    plurals
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
      singulars
      1. PTAnswer
    2. PO
      singulars
      1. PTAnswer
    3. PO
      singulars
      1. PTAnswer
    1. VO
      singulars
      1. PODo I have to bind a UDP socket in my client program to receive data? (I always get WSAEINVAL)
      1. This table or related slice is empty.
      1. VTUpMod
    2. VO
      singulars
      1. PODo I have to bind a UDP socket in my client program to receive data? (I always get WSAEINVAL)
      1. This table or related slice is empty.
      1. VTUpMod
    3. VO
      singulars
      1. PODo I have to bind a UDP socket in my client program to receive data? (I always get WSAEINVAL)
      1. USJ Fritsch
      1. VTFavorite
    1. This table or related slice is empty.
 

Querying!

 
Guidance
A row detail

Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

Related data can be related in a to-one or a to-many fashion. Captions of data related in a to-many fashion link to a list view showing a filtered view of the table.

Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

SQuiL has stopped working due to an internal error.

If you are curious you may find further information in the browser console, which is accessible through the devtools (F12).

Reload