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
descendents 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(3C), 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(3C)
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(4). Values for these variables may be
obtained programatically using the pmGetConfig(3) function.
SEE ALSO
PMAPI(3), pmGetChildren(3), pmGetConfig(3), pmLoadASCIINameSpace(3),
pmLoadNameSpace(3), pmLookupName(3), pmNameID(3), pcp.conf(4),
pcp.env(4) and pmns(4).
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.