PPS object types

Updated: May 06, 2022

Device publishers write device information to multiple PPS objects in fixed locations. Applications can monitor these objects to learn of device updates and to retrieve information that enables access to device contents.

Publishers output the following types of PPS objects for each device:
Type Description Location
Device information object
Contains physical and logical connectivity information specific to the device's hardware type. This information might include:
  • device's vendor ID
  • mediastore type
  • product serial number
  • details on temperature and drive mechanism state
  • slot information
Device control object

Accepts commands for performing device actions, such as toggling the power on a USB hub port or ejecting a disc.

Can also contain command outcomes, depending on the publisher.

Note: The device control objects are PPS server objects. For information on using server objects, see the Persistent Publish/Subscribe Developer's Guide.
/pps/qnx/device/type_ctrl, where type is either usb or cd0
Driver object Contains driver information, such as the process name and ID (pid), and a reference to the device information object associated with the driver /pps/qnx/driver/
Mount object
Contains information on the device's filesystem, including:
  • mountpoint
  • filesystem type
  • partition label
  • other hardware-specific fields