opensolaris man page for qassociate

qassociate(9F)						   Kernel Functions for Drivers 					    qassociate(9F)

NAME
       qassociate - associate STREAMS queue with driver instance

SYNOPSIS
       #include <sys/types.h>
       #include <sys/stream.h>
       #include <sys/stropts.h>
       #include <sys/ddi.h>
       #include <sys/sunddi.h>

       int qassociate(queue_t *q, int instance

INTERFACE LEVEL
       Solaris DDI specific (Solaris DDI).

PARAMETERS
       queue_t *q      Pointer to a queue(9S) structure. Either the read or write queue can be used.

       int instance    Driver instance number or -1.

DESCRIPTION
       The  qassociate()  function  must  be  used  by	DLPI  style  2	device drivers to manage the association between STREAMS queues and device
       instances. The gld(7D) does this automatically on behalf of drivers based on it. It is recommended that the gld(7D)  be	used  for  network
       device drivers whenever possible.

       The  qassociate()  function associates the specified STREAMS queue with the specified instance of the bottom driver in the queue. Upon suc-
       cessful return, the stream is associated with the instance with any prior association dissolved.

       A DLPI style 2 driver calls qassociate() while processing the DL_ATTACH_REQ message. The driver is also expected  to  call  this  interface
       while performing stream associations through other means, such as ndd(1M) ioctl commands.

       If instance is -1, the stream is left unassociated with any hardware instance.

       If the interface returns failure, the stream is not associated with the specified instance. Any prior association is left untouched.

       The  interface  typically  fails  because  of  failure to locate and attach the device instance. The interface never fails if the specified
       instance is -1.

CONTEXT
       The qassociate() function can be called from the stream's put(9E) entry point.

RETURN VALUES
       0     Success.

       -1    Failure.

EXAMPLES
       DLPI style 2 network driver DL_ATTACH_REQ code specifies:

	 if (qassociate(q, instance) != 0)
			 goto fail;

       The association prevents Dynamic Reconfiguration (DR) from detaching the instance.

       DLPI style 2 network driver DL_DETACH code specifies:

	 (void) qassociate(q, -1);

       This dissolves the queue's association with any device instance.

       DLPI style 2 network driver open(9E) code must call:

	 qassociate(q, -1);

       This informs the framework that this driver has been modified to be DDI-compliant.

SEE ALSO
       dlpi(7P), gld(7D), open(9E), put(9E), ddi_no_info(9F), queue(9S)

SunOS 5.11							    01 Feb 2007 						    qassociate(9F)