Go

Socket Send/Receive 16-bit Integers

Demonstrates sending and receiving 16-bit integers over a socket connection using either big-endian or little-endian byte ordering. Go

    success := false

    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    sock := chilkat.NewSocket()

    // --------------------------------------------------------------------
    // This example uses the public TCP echo service at https://tcpbin.com/
    // --------------------------------------------------------------------

    useTls := false
    port := 4242
    maxWaitMs := 5000
    success = sock.Connect("tcpbin.com",port,useTls,maxWaitMs)
    if success == false {
        fmt.Println(sock.LastErrorText())
        sock.DisposeSocket()
        return
    }

    // Wait a max of 2 seconds for a response..
    sock.SetMaxReadIdleMs(2000)

    // Send a 16-bit integer using big-endian byte ordering (also called network byte order)
    // 12022 decimal = 2EF6 hex
    value := 12022
    bigEndian := true
    sock.SendInt16(value,bigEndian)
    // Send it again, because we'll read it two different ways..
    sock.SendInt16(value,bigEndian)

    // The tcpbin.com echo server only echoes after receiving an LF (linefeed char)
    sock.SendByte(10)

    // Let's see hex values of the 2 bytes sent in network byte order (big-endian)
    // (The echo server sends back exactly the bytes received.)
    hexStr := sock.ReceiveNBytesENC(2,"hex")

    // In the big-ending byte order, the byte order is most significant byte to least significant,
    // therefore we should see the bytes in the order 0x2E 0xF6.
    fmt.Println("Expecting big-endian 2EF6")
    fmt.Println(*hexStr)

    // Let's read directly to an integer..
    success = sock.ReceiveInt16(bigEndian,true)
    fmt.Println("Expecting 12022")
    fmt.Println("Received: ", sock.ReceivedInt())

    // Consume the LF that gets echoed back..
    sock.ReceiveByte(true)

    // --------------------------------------------------------------------
    // Let's do the same thing, but with little-endian byte ordering.

    fmt.Println("----")

    // 12022 decimal = 2EF6 hex, but little-endian byte ordering will send the bytes in the order 0xF6 0x2E
    value = 12022
    bigEndian = false
    sock.SendInt16(value,bigEndian)
    sock.SendInt16(value,bigEndian)
    sock.SendByte(10)

    hexStr = sock.ReceiveNBytesENC(2,"hex")

    fmt.Println("Expecting little-endian F62E")
    fmt.Println(*hexStr)

    success = sock.ReceiveInt16(bigEndian,true)
    fmt.Println("Expecting 12022")
    fmt.Println("Received: ", sock.ReceivedInt())

    // Consume the LF that gets echoed back..
    sock.ReceiveByte(true)

    sock.Close(1000)

    // Output:

    // Expecting big-endian 2EF6
    // 2EF6
    // Expecting 12022
    // Received: 12022
    // ----
    // Expecting little-endian F62E
    // F62E
    // Expecting 12022
    // Received: 12022

    sock.DisposeSocket()