Send a 4-byte Length Prefix over a Socket

See more Socket/SSL/TLS Examples

Demonstrates Socket.SendCount, which sends a four-byte length prefix in network byte order. This is typically used to tell the peer how many bytes follow.

#include <C_CkSocket.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSocket socket;
    BOOL bTls;
    int maxWaitMs;
    int messageLength;

    success = FALSE;

    socket = CkSocket_Create();

    //  Connect to the server using TLS.
    bTls = TRUE;
    maxWaitMs = 5000;
    success = CkSocket_Connect(socket,"example.com",5000,bTls,maxWaitMs);
    if (success == FALSE) {
        printf("%s\n",CkSocket_lastErrorText(socket));
        CkSocket_Dispose(socket);
        return;
    }

    //  Send a four-byte length prefix in network byte order.  A common framing pattern is to send the
    //  number of bytes in a message before the message itself, so the peer knows exactly how many bytes
    //  to read.
    messageLength = 512;
    success = CkSocket_SendCount(socket,messageLength);
    if (success == FALSE) {
        printf("%s\n",CkSocket_lastErrorText(socket));
        CkSocket_Dispose(socket);
        return;
    }

    printf("Length prefix sent.\n");


    CkSocket_Dispose(socket);

    }