The Open Systems File interface (OSFI) provides a standard mechanism for handling nonfile entities as if they were standard D3 files.
The high-level interface is through Super Q-Pointers that indicate the host name and some identifier of the data in the remote environment.
The OSFI uses the specified host information to access one of many low-level drivers, which opens a direct channel into the remote environment. All standard D3 file system calls are translated into a limited number of internal commands that all low-level drivers understand and can translate into the appropriate operation in their respective environments.
The low-level drivers can be user-written or standard ones as provided by Rocket, including a D3 remote file driver, a UNIX remote file driver, and a D3 spooler driver.