PPS object types

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 can output the following types of PPS object for each device:

Type Description Location
Device 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

Contains commands specifying device actions to perform, such as toggling the power on a port of a USB hub or ejecting a disc.

Can also contain command outcomes, depending on the publisher type.

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 object associated with the driver. /pps/qnx/driver/
Mount object
Contains information on the device's filesystem, including:
  • mountpoint
  • filesystem type
  • partition label
  • other fields specific to the hardware type