v7 man page for pkon

PKON(2) 							System Calls Manual							   PKON(2)

NAME
       pkon, pkoff - establish packet protocol

SYNOPSIS
       pkon(fd, size)

       pkoff(fd)

DESCRIPTION
       Pkon  establishes  packet  protocol  (see  pk(4)) on the open character special file whose file descriptor is fd.  Size is a desired packet
       size, a power of 2 in the range 32<=size<=4096.	The size is negotiated with a remote packet driver, and a possibly smaller  actual  packet
       size is returned.

       An asynchronous line used for packet communication should be in raw mode; see tty(4).

       Pkoff turns off the packet driver on the channel whose file descriptor is fd.

SEE ALSO
       pk(4), pkopen(3), tty(4), signal(2)

DIAGNOSTICS
       Pkon returns -1 if fd does not describe an open file, or if packet communication cannot be established.

       Pkoff returns -1 for an unknown file descriptor.

       Writing on a packet driver link that has been shut down by close or pkoff at the other end raises signal SIGPIPE in the writing process.

																	   PKON(2)