Kernel Functions for Drivers            ldiaddeventhandler(9F)



NAME
     ldiaddeventhandler  -  add  NDI  event  service  callback
     handler

SYNOPSIS
     #include 

     int ldiaddeventhandler(ldihandlet lh, ddieventcookiet ec,
          void (*handler)(ldihandlet, ddieventcookiet,
          void *, void *) void *arg, ldicallbackidt *id);


INTERFACE LEVEL
     Obsolete

PARAMETERS
     ldihandlet lh

         Layered handle representing event notification device.


     ddieventcookiet ec

         Cookie returned from call to ldigeteventcookie(9F).


     void (*handler)(ldihandlet, ddieventcookiet, void *,
     void *)

         Callback handler for NDI event service notification.


     void *arg

         Pointer to opaque data supplied  by  caller.  Typically,
         this  is  a  pointer  to  the layered driver's softstate
         structure.


     ldicallbackidt *id

         Pointer to registration id, where a unique  registration
         id  is  returned. Registration id must be saved and used
         when calling ldiremoveeventhandler(9F) to  unregister
         a callback handler.


DESCRIPTION
     This function is obsolete and is only maintained for  compa-
     tibility.  Use of this function is strongly discouraged. For
     equivalent functionality provided  by  new  interfaces,  see
     ldievgetcookie(9F) and ldievregistercallbacks(9F).



SunOS 5.11          Last change: 21 Aug 2007                    1






Kernel Functions for Drivers            ldiaddeventhandler(9F)



     The ldiaddeventhandler() function adds a callback handler
     to be invoked at the occurance of the event specified by the
     cookie. Adding a callback handler is also known as subscrib-
     ing  to  an event. Upon successful subscription, the handler
     is invoked when the event occurs.  You  can  unregister  the
     handler by using ldiremoveeventhandler(9F).


     An instance  of  a  layered  driver  can  register  multiple
     handlers  for  an  event  or  a  single handler for multiple
     events. Callback order is not defined and should be  assumed
     to be random.


     The routine handler is invoked with the following arguments:

     ldihandlet lh         Layered handle representing the dev-
                             ice for which the event notification
                             is requested.


     ddieventcookiet ec    Structure  describing   event   that
                             occurred.


     void *arg               Opaque data pointer provided by  the
                             driver during callback registration.


     void *impldata         Pointer  to  event   specific   data
                             defined   by   the   framework  that
                             invokes the callback function.


RETURN VALUES
     DISUCES    Callback handler registered successfully.


     DIFAILURE    Failed to register callback handler. Possible
                    reasons  include  lack  of resources or a bad
                    cookie.


CONTEXT
     The ldiaddeventhandler() function can be called from user
     and kernel contexts only.

SEE ALSO
     ldievgetcookie(9F),        ldievregistercallbacks(9F),
     ldigeteventcookie(9F), ldiremoveeventhandler(9F)





SunOS 5.11          Last change: 21 Aug 2007                    2






Kernel Functions for Drivers            ldiaddeventhandler(9F)



     Writing Device Drivers

NOTES
     Layered drivers must remove all registered callback handlers
     for a device instance, represented by the layered handle, by
     calling  ldiremoveeventhandler(9F)  before  the   layered
     driver's detach(9E) routine completes.
















































SunOS 5.11          Last change: 21 Aug 2007                    3