connld(7M)							  STREAMS Modules							connld(7M)

NAME

       connld - line discipline for unique stream connections

SYNOPSIS

       #include </sys/steam.h>

       int ioctl(fd,I_PUSH,"connld");

DESCRIPTION

       connld  is  a  STREAMS-based  module  that  provides  unique  connections  between  server and client processes. It can only be pushed (see
       streamio(7I)) onto one end of a STREAMS-based
	pipe that may subsequently be attached to a name in the file system name space with  fattach(3C). After the pipe end is  attached,  a  new
       pipe  is  created internally when an  originating process attempts to  open(2) or  creat(2) the file system name. A file descriptor for one
       end of the new pipe is packaged into a message identical to that for the ioctl  I_SENDFD (see  streamio(7I)) and is transmitted	along  the
       stream to the server process on the  other end. The originating process is blocked until the server responds.

       The  server  responds to the  I_SENDFD request by accepting the file descriptor through the  I_RECVFD ioctl message. When this happens, the
       file descriptor associated with the other end of the new pipe is transmitted to the originating process as  the	file  descriptor  returned
       from open(2) or creat(2).

       If the server does not respond to the  I_SENDFD request, the stream that the connld module is pushed on becomes uni-directional because the
       server  will not be able to retrieve any data off the stream until the  I_RECVFD request is issued. If  the  server  process  exits  before
       issuing the  I_RECVFD request, the open(2) or the creat(2) invocation will fail and return -1 to the originating process.

       When the connld module is pushed onto a pipe, it ignores messages going back and forth  through the pipe.

ERRORS

       On success, an open of connld returns 0. On failure, errno is set to the following values:

       EINVAL	       A  stream  onto	which  connld  is being pushed is not a pipe or the pipe does not have a write queue pointer pointing to a
		       stream head read queue.

       EINVAL	       The other end of the pipe onto which connld is being pushed is linked under a multiplexor.

       EPIPE	       connld is being pushed onto a pipe end whose other end is no longer there.

       ENOMEM	       An internal pipe could not be created.

       ENXIO	       An  M_HANGUP message is at the stream head of the pipe onto which connld is being pushed.

       EAGAIN	       Internal data structures could not be allocated.

       ENFILE	       A file table entry could not be allocated.

SEE ALSO

       creat(2), open(2), fattach(3C), streamio(7I)

       STREAMS Programming Guide

SunOS 5.10							    3 May 2004								connld(7M)