Manual Pages for UNIX Operating System command usage for man ddi_prop_exists

Kernel Functions for Drivers                  ddi_prop_exists(9F)



NAME
     ddi_prop_exists - check for the existence of a property

SYNOPSIS
     #include 
     #include 



     int ddi_prop_exists(dev_t match_dev, dev_info_t *dip, uint_t flags,
          char *name);


INTERFACE LEVEL
     Solaris DDI specific (Solaris DDI).

PARAMETERS
     match_dev     Device  number  associated  with  property  or
                   DDI_DEV_T_ANY.


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


     flags         Possible flag values are some combination of:

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


                   DDI_PROP_NOTPROM      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
     ddi_prop_exists() checks for the  existence  of  a  property
     regardless  of the property value data type.


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




SunOS 5.11          Last change: 22 May 1995                    1






Kernel Functions for Drivers                  ddi_prop_exists(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 DDI_PROP_NOTPROM is not  set,  search  the  PROM
              properties (if they exist).

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

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


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


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

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

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

EXAMPLES
     Example 1 : Using ddi_prop_exists()


     The   following   example   demonstrates    the    use    of
     ddi_prop_exists().


       /*
            * Enable "whizzy" mode if the "whizzy-mode" property exists
            */
            if (ddi_prop_exists(xx_dev, xx_dip, DDI_PROP_NOTPROM,
                    "whizzy-mode") == 1) {
                  xx_enable_whizzy_mode(xx_dip);



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Kernel Functions for Drivers                  ddi_prop_exists(9F)



            } else {
                  xx_disable_whizzy_mode(xx_dip);
            }


SEE ALSO
     ddi_prop_get_int(9F),                   ddi_prop_lookup(9F),
     ddi_prop_remove(9F), ddi_prop_update(9F)


     Writing Device Drivers












































SunOS 5.11          Last change: 22 May 1995                    3