NAME

       pmGetChildren - return the descendent nodes of a PMNS node

C SYNOPSIS

       #include <pcp/pmapi.h>

       int pmGetChildren(const char *name, char ***offspring);

       cc ... -lpcp

DESCRIPTION

       Given a fully qualified pathname to a node in the current Performance Metrics Name Space (PMNS), as iden‐
       tified  by name, pmGetChildren 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.

       Normally, pmGetChildren will return the number of descendent names discovered, else a value less than ze‐
       ro 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 pmGetChildren with a single call to malloc(3), and it is  the  responsibility
       of the pmGetChildren caller to free(offspring) to release the space when it is no longer required.

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

DIAGNOSTICS

       PM_ERR_NOPMNS
              Failed to access a PMNS for operation.  Note that if the application hasn't a  priori  called  pm‐
              LoadNameSpace(3)  and wants to use the distributed PMNS, then a call to pmGetChildren 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.

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), pmGetChildrenStatus(3), pmGetConfig(3), pmLoadASCIINameSpace(3), pmLoadNameSpace(3),  pmLookup‐
       Name(3), pmNameID(3), pcp.conf(5), pcp.env(5) and PMNS(5).

Performance Co-Pilot                                   PCP                                      PMGETCHILDREN(3)