An easy way to use the standard communication functions for transferring data over the IR port is to use the IrCOMM mode.
An IrCOMM port is a simulated port and not a real device, which causes some differences with a raw IR port. For instance, an application cannot configure an IrCOMM port. Windows CE transparently uses IrSock to configure an IrCOMM port to meet the IrDA standard. When the GetCommState function is called to retrieve the communication settings for an IrCOMM port, the DCB structure returned contains zeros. But, with the IR link managed by ISock, it tackles important issues such as signal collision, signal interruption, and remote device detection. Relieving an application of these tasks simplifies programming IR communications.
One limitation of IrCOMM is that only two devices can be connected simultaneously.
To determine the IrCOMM port, open the HKEY_LOCAL_MACHINE\Drivers\Builtin\IrCOMM key and query the Index subkey.