ReceiveSb Returns Only the Immediately Available Data

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Demonstrates that Socket.ReceiveSb returns only the data immediately available and not the entire response. The example connects to chilkatsoft.com over TLS and requests big_helloWorld.txt, a large text file of roughly 74,000 lines. A single ReceiveSb call returns just the first portion of the response, and the example reports how many characters were received compared with the total size given by the response Content-Length header.

    success := false

    socket := chilkat.NewSocket()

    //  Connect to chilkatsoft.com over TLS.
    bTls := true
    maxWaitMs := 5000
    success = socket.Connect("chilkatsoft.com",443,bTls,maxWaitMs)
    if success == false {
        fmt.Println(socket.LastErrorText())
        socket.DisposeSocket()
        return
    }

    socket.SetStringCharset("utf-8")

    //  Send an HTTP GET request for big_helloWorld.txt, a large text file of roughly 74,000 lines of
    //  "Hello World!".  This uses a minimal HTTP request only to exercise ReceiveSb against a public
    //  server -- for real HTTP work, use the Chilkat Http, Rest, or HttpCurl classes instead.
    httpReq := "GET /big_helloWorld.txt HTTP/1.1\r\nHost: chilkatsoft.com\r\nConnection: close\r\n\r\n"
    success = socket.SendString(httpReq)
    if success == false {
        fmt.Println(socket.LastErrorText())
        socket.DisposeSocket()
        return
    }

    //  Call ReceiveSb a single time.  It returns only the bytes that are immediately available --
    //  typically just the first network packet -- and does NOT wait for the entire response to arrive.
    sb := chilkat.NewStringBuilder()
    success = socket.ReceiveSb(sb)
    if success == false {
        fmt.Println(socket.LastErrorText())
        socket.DisposeSocket()
        sb.DisposeStringBuilder()
        return
    }

    //  The response begins with HTTP headers.  The Content-Length header gives the total size, in bytes,
    //  of the response body.
    contentLength := sb.GetBetween("Content-Length: ","\r\n")
    if sb.LastMethodSuccess() == false {
        fmt.Println(sb.LastErrorText())
        socket.DisposeSocket()
        sb.DisposeStringBuilder()
        return
    }

    //  Compare what this single ReceiveSb returned against the full size of the expected response.  The
    //  received amount is only a small fraction of the total.
    fmt.Println("Characters received so far (headers + partial body): ", sb.Length())
    fmt.Println("Expected response body size (Content-Length): ", *contentLength, " bytes")

    //  A single ReceiveSb call returns whatever is currently available, so it cannot indicate whether the
    //  full response has arrived.  This makes it difficult to know when a response is complete: the
    //  application must either know how many bytes to expect (for example from a Content-Length header or
    //  an application-defined length prefix) and keep receiving until that many bytes are collected, or
    //  keep receiving until the peer closes the connection.

    socket.DisposeSocket()
    sb.DisposeStringBuilder()