PHP

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. Chilkat2 PHP

<?php

use Chilkat2\Socket;

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

$sock = new Socket();

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

$useTls = false;
$port = 4242;
$maxWaitMs = 5000;
try {
    $sock->Connect('tcpbin.com', $port, $useTls, $maxWaitMs);
} catch (\Chilkat2\Exception $e) {
    echo $e->getMessage(), "\n";
    exit;
}

// Wait a max of 2 seconds for a response..
$sock->MaxReadIdleMs = 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.
echo "Expecting big-endian 2EF6\n";
echo $hexStr, "\n";

// Let's read directly to an integer..
$sock->ReceiveInt16($bigEndian, true);
echo "Expecting 12022\n";
echo 'Received: ', $sock->ReceivedInt, "\n";

// Consume the LF that gets echoed back..
$sock->ReceiveByte(true);

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

echo "----\n";

// 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');

echo "Expecting little-endian F62E\n";
echo $hexStr, "\n";

$sock->ReceiveInt16($bigEndian, true);
echo "Expecting 12022\n";
echo 'Received: ', $sock->ReceivedInt, "\n";

// 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