The DlnOpenDevice() function allows you to open all available devices in a loop. This function accepts two parameters - an index number of the adapter to open and the pointer to the variable that receives the device handle. The deviceNumber parameter is zero-based.
You can call the DlnGetDeviceCount() function to obtain the number of available devices, and then call the DlnOpenDevice() function in a loop to open all devices as illustrated in the following code snippet:
HDLN handle; DLN_RESULT result = DlnOpenDevice(0, &handle);
You should make no assumptions about the association between deviceNumber parameter and the specific hardware. You can call the DlnGetDeviceSn() or DlnGetDeviceId() function to identify the device after it is open, or use one of the functions listed in the next chapters to open a specific device.
The DlnOpenDevice() and DlnGetDeviceCount() functions enumerate and open devices currently accessible to the DLN library - the device should be accessible to the computer where the DLN Server is running and your application should be connected to this DLN Server. In case of Direct Mode, the library itself establishes connections to the devices accessible to local PC. You can treat this as if the library is connected to the DLN Server running on the same PC where the application is launched.
The connection to the DLN Server is established by calling the DlnConnect() function, providing server IP and TCP port. After connection is established you get access to all devices accessible to the PC where the server is running:
Devices connected to the USB port of this computer.
Devices located in the range of Bluetooth Low Energy (BLE) connectivity to this computer.