Kernel Functions for Drivers                  ddipropexists(9F)



NAME
     ddipropexists - check for the existence of a property

SYNOPSIS
     #include 
     #include 



     int ddipropexists(devt matchdev, devinfot *dip, uintt flags,
          char *name);


INTERFACE LEVEL
     Solaris DI specific (Solaris DI).

PARAMETERS
     matchdev     Device  number  associated  with  property  or
                   DIDEVTANY.


     dip           Pointer to the  device  info  node  of  device
                   whose property list should be searched.


     flags         Possible flag values are some combination of:

                   DIPROPDONTPAS     Do not pass  request  to
                                         parent  device  informa-
                                         tion node  if  the  pro-
                                         perty  is not found.


                   DIPROPNOTPROM      Do  not  look  at   PROM
                                         properties  (ignored  on
                                         platforms  that  do  not
                                         support    PROM  proper-
                                         ties).



     name          String containing the name of the property.


DESCRIPTION
     ddipropexists() checks for the  existence  of  a  property
     regardless  of the property value data type.


     Properties are searched for based  on  the  dip,  name,  and
     matchdev. The property search order is as follows:




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Kernel Functions for Drivers                  ddipropexists(9F)



         1.   Search software properties created by the driver.

         2.   Search the software properties created by the  sys-
              tem (or nexus nodes in the device info tree).

         3.   Search the driver global properties list.

         4.   If DIPROPNOTPROM is not  set,  search  the  PROM
              properties (if they exist).

         5.   If DIPROPDONTPAS is not set, pass this  request
              to the parent device information node.

         6.   Return 0 if not found and 1 if found.


     Usually, the matchdev argument should be set to the  actual
     device  number  that this property is associated with.  How-
     ever, if the   matchdev  argument  is  DIDEVTANY,  then
     ddipropexists()  will match the request  regardless of the
     matchdev the property was created with.  That is the  first
     property  whose  name  matches  name will be returned.  If a
     property was created with  matchdev set to   DIDEVTNONE
     then  the  only  way  to  look  up  this  property is with a
     matchdev set to DIDEVTANY. PROM properties  are  always
     created with matchdev set to DIDEVTNONE.


     name must always be set to the name of  the  property  being
     looked up.

RETURN VALUES
     ddipropexists() returns  1 if the property exists  and   0
     otherwise.

CONTEXT
     These functions can be called from user or kernel context.

EXAMPLES
     Example 1 : Using ddipropexists()


     The   following   example   demonstrates    the    use    of
     ddipropexists().


       /*
            * Enable "whizzy" mode if the "whizzy-mode" property exists
            */
            if (ddipropexists(xxdev, xxdip, DIPROPNOTPROM,
                    "whizzy-mode") == 1) {
                  xxenablewhizzymode(xxdip);



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Kernel Functions for Drivers                  ddipropexists(9F)



            } else {
                  xxdisablewhizzymode(xxdip);
            }


SEE ALSO
     ddipropgetint(9F),                   ddiproplookup(9F),
     ddipropremove(9F), ddipropupdate(9F)


     Writing Device Drivers












































SunOS 5.11          Last change: 22 May 1995                    3