NAME¶
pmUseContext - change current PMAPI context
C SYNOPSIS¶
#include <pcp/pmapi.h>
int pmUseContext(int
handle);
cc ... -lpcp
DESCRIPTION¶
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
pmUseContext causes the current PMAPI context to be set to the
context identified by
handle. The value of
handle must be one
returned from an earlier call to
pmNewContext(3) or
pmDupContext(3).
Below the PMAPI, all contexts used by an application are saved in their most
recently modified state, so
pmUseContext restores the context to the
state it was in the last time the context was used, not the state of the
context when it was established.
SEE ALSO¶
PMAPI(3),
pmDestroyContext(3),
pmDupContext(3),
pmNewContext(3) and
pmWhichContext(3).
DIAGNOSTICS¶
PM_ERR_NOCONTEXT
- handle does not identify a valid PMAPI context
