A client application communicates with the proximity device through a defined set of I/O control codes sent to an open handle.
Each publication and each subscription is represented as an open handle to the driver. Therefore, M publications and N subscriptions would equate to M+N open handles to the driver. The Windows I/O Manager will enforce reasonable handle count limits on processes.
A generic file handle is opened for sending non-publication and non-subscription requests to the driver. This type of handle must be accepted. The client will use this handle to determine the Maximum Message Size and the Transmission Rate of the driver.
The IOCTLs supporting the proximity device driver interface are defined in Nfpdev.h. These IOCTLs are described in the Proximity Driver IOCTLs reference section. The control codes are defined with the following attributes.
The following table describes the reserved and vender specific control code ranges.
|Type||Range Start||Range End|
Build date: 11/16/2013