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PMC_START(3) FreeBSD Library Functions Manual PMC_START(3)
NAME pmc_start, pmc_stop - start and stop a PMC
LIBRARY Performance Counters Library (libpmc, -lpmc)
SYNOPSIS #include <pmc.h>
int pmc_start(pmc_id_t pmc);
int pmc_stop(pmc_id_t pmc);
DESCRIPTION These functions are used to start and stop a PMC.
Function pmc_start() starts the PMC specified by argument pmc. If the specified PMC has process scope and has not been attached to any targets, it will be attached to the current process.
Function pmc_stop() stops the PMC specified by argument pmc.
RETURN VALUES Upon successful completion, the value 0 is returned; otherwise the value -1 is returned and the global variable errno is set to indicate the error.
ERRORS A call to these functions may fail with the following errors:
[EDOOFUS] Function pmc_start() specified a PMC that requires a log file and no log file was configured.
[EINVAL] The specified PMC is in the process of being deleted.
[EINVAL] Function pmc_stop() specified a PMC that was never started.
[ENXIO] The specified PMC had system scope and its associated CPU was disabled or absent.
SEE ALSO pmc(3), hwpmc(4)
FreeBSD 14.0-RELEASE-p11 September 22, 2008 FreeBSD 14.0-RELEASE-p11