.TH PKON 2
.UC
.SH NAME
pkon, pkoff \- establish packet protocol
.SH SYNOPSIS
.B pkon(fd, size)
.PP
.B pkoff(fd)
.SH DESCRIPTION
.I Pkon
establishes packet protocol (see
.IR pk (4))
on the open character special file whose file
descriptor is
.I fd.
.I Size
is a desired packet size, a power of 2 in the range
.RI 32\(<= size \(<=4096.
The size is negotiated with a remote packet driver,
and a possibly smaller actual packet size is returned.
.PP
An asynchronous line used for packet
communication should be in raw mode;
see
.IR tty (4).
.PP
.I Pkoff
turns off the packet driver on the channel whose
file descriptor is
.I fd.
.SH RETURN VALUE
Upon successful completion, a value of 0 is returned.  Otherwise, a
value of \-1 is returned and
.I errno
is set to indicate the error.
.SH SEE ALSO
signal(2), pkopen(3), pk(4), tty(4)
.SH BUGS
The packet protocol is not supported by the operating system.