src/Protocol/Protocol.php
public static function isSystemLittleEndian(): bool
    {
        // If we don't know if our system is big endian or not yet...
        if (self::$isLittleEndianSystem === null) {
            [$endianTest] = array_values(unpack('L1L', pack('V', 1)));

            self::$isLittleEndianSystem = (int) $endianTest === 1;
        }

        return self::$isLittleEndianSystem;
    }
public static function isSystemLittleEndian(): bool
    {
        // If we don't know if our system is big endian or not yet...
        if (self::$isLittleEndianSystem === null) {
            [$endianTest] = array_values(unpack('L1L', pack('V', 1)));

            self::$isLittleEndianSystem = (int) $endianTest === 1;
        }

        return self::$isLittleEndianSystem;
    }
Determines if the computer currently running this code is big endian or little endian.