C

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. C

#include <C_CkSocket.h>

void ChilkatSample(void)
    {
    BOOL success;
    HCkSocket sock;
    BOOL useTls;
    int port;
    int maxWaitMs;
    int value;
    BOOL bigEndian;
    const char *hexStr;

    success = FALSE;

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

    sock = CkSocket_Create();

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

    useTls = FALSE;
    port = 4242;
    maxWaitMs = 5000;
    success = CkSocket_Connect(sock,"tcpbin.com",port,useTls,maxWaitMs);
    if (success == FALSE) {
        printf("%s\n",CkSocket_lastErrorText(sock));
        CkSocket_Dispose(sock);
        return;
    }

    //  Wait a max of 2 seconds for a response..
    CkSocket_putMaxReadIdleMs(sock,2000);

    //  Send a 16-bit integer using big-endian byte ordering (also called network byte order)
    //  12022 decimal = 2EF6 hex
    value = 12022;
    bigEndian = TRUE;
    CkSocket_SendInt16(sock,value,bigEndian);
    //  Send it again, because we'll read it two different ways..
    CkSocket_SendInt16(sock,value,bigEndian);

    //  The tcpbin.com echo server only echoes after receiving an LF (linefeed char)
    CkSocket_SendByte(sock,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 = CkSocket_receiveNBytesENC(sock,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.
    printf("Expecting big-endian 2EF6\n");
    printf("%s\n",hexStr);

    //  Let's read directly to an integer..
    success = CkSocket_ReceiveInt16(sock,bigEndian,TRUE);
    printf("Expecting 12022\n");
    printf("Received: %d\n",CkSocket_getReceivedInt(sock));

    //  Consume the LF that gets echoed back..
    CkSocket_ReceiveByte(sock,TRUE);

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

    printf("----\n");

    //  12022 decimal = 2EF6 hex, but little-endian byte ordering will send the bytes in the order 0xF6 0x2E
    value = 12022;
    bigEndian = FALSE;
    CkSocket_SendInt16(sock,value,bigEndian);
    CkSocket_SendInt16(sock,value,bigEndian);
    CkSocket_SendByte(sock,10);

    hexStr = CkSocket_receiveNBytesENC(sock,2,"hex");

    printf("Expecting little-endian F62E\n");
    printf("%s\n",hexStr);

    success = CkSocket_ReceiveInt16(sock,bigEndian,TRUE);
    printf("Expecting 12022\n");
    printf("Received: %d\n",CkSocket_getReceivedInt(sock));

    //  Consume the LF that gets echoed back..
    CkSocket_ReceiveByte(sock,TRUE);

    CkSocket_Close(sock,1000);

    //  Output:

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


    CkSocket_Dispose(sock);

    }