fd = open ("/dev/streams/dlb", O_RDWR, 0);
The dlb STREAMS pseudodevice driver provides a communication path between BSD-style device drivers and STREAMS protocol stacks. The dlb STREAMS pseudodevice driver is the Stream end in a Stream that communicates with BSD-based device drivers.
When the /dev/streams/dlb character device is open, a Stream is constructed between a Stream head and the dlb pseudodevice driver. After the Stream that is intended to communicate with the BSD-based driver or drivers is created, the protocol module or modules can be pushed onto it.
Tru64 UNIX supports a subset of the Data Link Provider Interface (DLPI) connectionless mode of communication. The attach DLPI primitive is required to associate a particular physical point of attachment (PPA) with a Stream in Tru64 UNIX's implementation of the style 2 provider.
On the write side, the dlb pseudodevice driver translates connectionless style 2 DLPI messages to the appropriate BSD ifnet interface messages. On the read side, the user-bound Service Access Point (SAP) messages received from a selected PPA over BSD based driver or drivers are sent upstream.
Network Programmer's Guide
specification in /usr/share/doclib/dlpi/dlpi.ps delim off