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.

IncludeFile "CkSocket.pb"

Procedure ChilkatExample()

    success.i = 0

    socket.i = CkSocket::ckCreate()
    If socket.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ;  Connect to the server using TLS.
    bTls.i = 1
    maxWaitMs.i = 5000
    success = CkSocket::ckConnect(socket,"example.com",5000,bTls,maxWaitMs)
    If success = 0
        Debug CkSocket::ckLastErrorText(socket)
        CkSocket::ckDispose(socket)
        ProcedureReturn
    EndIf

    ;  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.i = 512
    success = CkSocket::ckSendCount(socket,messageLength)
    If success = 0
        Debug CkSocket::ckLastErrorText(socket)
        CkSocket::ckDispose(socket)
        ProcedureReturn
    EndIf

    Debug "Length prefix sent."


    CkSocket::ckDispose(socket)


    ProcedureReturn
EndProcedure