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pmgetchildrenstatus(3)

NAME

   pmGetChildrenStatus  -  return  the descendent nodes of a PMNS node and
   their respective status

C SYNOPSIS

   #include <pcp/pmapi.h>

   int pmGetChildrenStatus(const char *name, char ***offspring,
           int **status);

   cc ... -lpcp

DESCRIPTION

   Given  a  fully qualified pathname to a node in the current Performance
   Metrics Name Space (PMNS), as identified by  name,  pmGetChildrenStatus
   returns  via  offspring  a  list  of  the  relative names of all of the
   immediate descendent nodes of name in the current PMNS.

   As a special case, if name is an empty string (i.e.""),  the  immediate
   descendants of the root node in the PMNS will be returned.

   If  status  is  not NULL, then pmGetChildrenStatus will also return the
   status of each child via status.  The status will  refer  to  either  a
   leaf node (with value PMNS_LEAF_STATUS ) or a non-leaf node (with value
   PMNS_NONLEAF_STATUS ).

   Normally, pmGetChildrenStatus will  return  the  number  of  descendent
   names  discovered, else a value less than zero for an error.  The value
   zero indicates that name is a valid metric  name,  i.e.  is  associated
   with a leaf node in the PMNS.

   The  resulting  list of pointers offspring and the values (the relative
   names)  that  the  pointers  reference  will  have  been  allocated  by
   pmGetChildrenStatus  with  a  single  call  to malloc(3), and it is the
   responsibility of the pmGetChildrenStatus caller to free(offspring)  to
   release  the  space when it is no longer required.  The same holds true
   for the status array.

   When an error occurs, or name is  a  leaf  node  (i.e.  the  result  of
   pmGetChildrenStatus  is  less  than one), both offspring and status are
   undefined (no space will have been allocated, and so calling free(3) is
   a singularly bad idea).

PCP ENVIRONMENT

   Environment variables with the prefix PCP_ are used to parameterize the
   file and directory names used by PCP.  On each installation,  the  file
   /etc/pcp.conf  contains  the  local  values  for  these variables.  The
   $PCP_CONF variable may be used to specify an alternative  configuration
   file,  as  described in pcp.conf(5).  Values for these variables may be
   obtained programmatically using the pmGetConfig(3) function.

SEE ALSO

   PMAPI(3),  pmGetChildren(3),  pmGetConfig(3),  pmLoadASCIINameSpace(3),
   pmLoadNameSpace(3),    pmLookupName(3),    pmNameID(3),    pcp.conf(5),
   pcp.env(5) and pmns(5).

DIAGNOSTICS

   PM_ERR_NOPMNS
          Failed to access  a  PMNS  for  operation.   Note  that  if  the
          application  hasn't a priori called pmLoadNameSpace(3) and wants
          to use the distributed PMNS, then a call to  pmGetChildrenStatus
          must be made inside a current context.

   PM_ERR_NAME
          The pathname name is not valid in the current PMNS

   PM_ERR_*
          Other  diagnostics  are for protocol failures when accessing the
          distributed PMNS.



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