PMDERIVEDCONTROL(3)        Library Functions Manual        PMDERIVEDCONTROL(3)

NAME
       pmGetDerivedControl, pmSetDerivedControl  - get and set controls for
       derived metrics

C SYNOPSIS
       #include <pcp/pmapi.h>

       int pmGetDerivedControl(int what, int *valuep);
       int pmSetDerivedControl(int what, int value);

       cc ... -lpcp

DESCRIPTION
       These routines may be used to influence the behaviour of the derived
       metric services that are activated for global derived metrics using
       pmRegisterDerived(3), pmRegisterDerivedMetric(3) and
       pmLoadDerivedConfig(3), or per-context derived metrics using
       pmAddDerived(3) and pmAddDerivedDerived(3).

       The what argument selects a control, the value argument provides a
       value for pmSetDerivedControl and the valuep argument is used to return
       the value for pmGetDerivedControl.

       The what argument has one of the following values:

       PCP_DERIVED_GLOBAL_LIMIT
              The maximum number of global derived metrics that may be
              defined.  The value -1 indicates no limit.

       PCP_DERIVED_CONTEXT_LIMIT
              The maximum number of per-context derived metrics that may be
              defined.  The value -1 indicates no limit.

       PCP_DERIVED_DEBUG_SYNTAX
              Debug diagnostics during parsing of derived metric expression.
              The value 1 enables the diagnostics, the value 0 disables them.

       PCP_DERIVED_DEBUG_SEMANTICS
              Debug diagnostics for semantic checks during the binding of
              metrics in the derived metric expression to the available
              metrics in a new PMAPI context.  The value 1 enables the
              diagnostics, the value 0 disables them.

       PCP_DERIVED_DEBUG_EVAL
              Debug diagnostics when derived metrics are used in PMAPI
              operations like pmFetch(3), pmGetChildren(3),
              pmGetChildrenStatus(3), pmLookupDesc(3), pmLookupName(3),
              pmNameAll(3), pmNameID(3) and pmTraversePMNS(3).

RETURN VALUES
       Both routines return 0 on success, else a value less than 0 that can be
       decoded using pmErrStr(3).

SEE ALSO
       PCPIntro(1), pmAddDerived(3), pmAddDerivedMetric(3), PMAPI(3),
       pmErrStr(3), pmLoadDerivedConfig(3), pmRegisterDerived(3),
       pmRegisterDerivedMetric(3) and PMNS(5).

Performance Co-Pilot                                       PMDERIVEDCONTROL(3)