pkon(2) [v7 man page]

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)

PKOPEN(3)						     Library Functions Manual							 PKOPEN(3)

NAME

       pkopen, pkclose, pkread, pkwrite, pkfail - packet driver simulator

SYNOPSIS

       char *pkopen(fd)

       pkclose(ptr)
       char *ptr;

       pkread(ptr, buffer, count)
       char *ptr, *buffer;

       pkwrite(ptr, buffer, count)
       char *ptr, *buffer;

       pkfail()

DESCRIPTION

       These  routines	are  a user-level implementation of the full-duplex end-to-end communication protocol described in pk(4).  If fd is a file
       descriptor open for reading and writing, pkopen carries out the initial synchronization and returns an identifying pointer.  The pointer is
       used as the first parameter to pkread, pkwrite, and pkclose.

       Pkread,	pkwrite and pkclose behave analogously to read, write and close(2).  However, a write of zero bytes is meaningful and will produce
       a corresponding read of zero bytes.

SEE ALSO

       pk(4), pkon(2)

DIAGNOSTICS

       Pkfail is called upon persistent breakdown of communication.  Pkfail must be supplied by the user.

       Pkopen returns a null (0) pointer if packet protocol can not be established.

       Pkread returns -1 on end of file, 0 in correspondence with a 0-length write.

BUGS

       This simulation of pk(4) leaves something to be desired in needing special read and write routines, and in  not	being  inheritable  across
       calls of exec(2).  Its prime use is on systems that lack pk.
       These functions use alarm(2); simultaneous use of alarm for other puposes may cause trouble.

								    deprecated								 PKOPEN(3)