An application using the
Performance Metrics Application Programming Interface (PMAPI)
may manipulate several concurrent contexts,
each associated with a source of performance metrics, e.g. pmcd(1)
on some host, or an archive log of performance metrics as created by
pmlogger(1).
Calling
pmContextUndef
causes the
current PMAPI context to be reset to undefined state which could be use
to prevent unintentional communication with PMCD.