BACnetWhoHas (FUN)

FUNCTION BACnetWhoHas : IEC_BACNET_STATUS

Sends a who-Has request.

Sends a BACnet Who-Has request to a local or remote device or network. This routine allows an application to discover BACnet Devices whose local databases contain a given named object, or a given Object Identifier. The I-Have service is used to respond to Who-Has service requests.

InOut:

Scope	Name	Type	Comment
Return	BACnetWhoHas	IEC_BACNET_STATUS	A status indicating whether the operation worked.
Input	pSourceAddress	POINTER TO IEC_BACNET_ADDRESS	If the BACnet application has only one device constructed and installed, this can be 0. In this case the MAC address of this device will be used. Otherwise this shall be the MAC address returned on device object construction.
	pDestinationAddress	POINTER TO IEC_BACNET_ADDRESS	This is the MAC address of the device to which the request should be sent.
	filterMin	IEC_BACNET_DWORD	Optional argument for the Who-Is request, which limit the lower range of Device instance numbers expected to respond to the Who-Is request. This argument is omitted from the request if both parameters have the value “BACNET_NO_FILTER” (use -1).
	filterMax	IEC_BACNET_DWORD	Optional argument for the Who-Is request, which limit the upper range of Device instance numbers expected to respond to the Who-Is request. This argument is omitted from the request if both parameters have the value “BACNET_NO_FILTER” (use -1).
	objectSpec	POINTER TO IEC_BACNET_WHO_HAS_PARAM	A pointer to a data structure which includes either the Object Identifier or Object Name of the object which is requested, and a tag field that indicates which of these two possibilities was chosen.