'\"macro stdmacro
.\"
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.TH PMUNREGISTERDERIVED 3 "" "Performance Co-Pilot"
.SH NAME
\f3pmUnregisterDerived\f1  \- unregister a derived metric
.SH "C SYNOPSIS"
.ft 3
.ad l
.hy 0
#include <pcp/pmapi.h>
.sp
int pmUnregisterDerived(char *\fIname\fP);
.sp
cc ... \-lpcp
.hy
.ad
.ft 1
.SH DESCRIPTION
Derived metrics provide a way of extending the Performance Metrics
Name Space (PMNS) with new metrics defined at the PCP client-side using
expressions over the existing performance metrics.
.PP
Global derived metrics are created by calling
.BR pmRegisterDerived (3),
.BR pmRegisterDerivedMetric (3)
or
.BR pmLoadDerivedConfig (3).
Per-context derived metrics are created by calling
.BR pmAddDerived (3)
or
.BR pmAddDerivedMetric (3).
.PP
.B pmUnregisterDerived
removes the definition of the derived metric
.I name
from the set of glabal derived metrics and from every active PMAPI context.
.SH DIAGNOSTICS
On success,
.B pmUnregisterDerived
returns a value greater than or equal to zero being
the number of contexts from which
.I name
was removed.
.PP
Othewise
.B pmUnregisterDerived
returns a PMAPI error and the application should call
.BR pmErrStr (3)
to retrieve the corresponding error message.
.SH SEE ALSO
.BR PCPIntro (1),
.BR PMAPI (3),
.BR pmAddDerived (3),
.BR pmAddDerivedMetric (3),
.BR pmErrStr (3),
.BR pmLoadDerivedConfig (3),
.BR pmRegisterDerived (3),
.BR pmRegisterDerivedMetric (3)
and
.BR PMNS (5).