PMC_ATTACH(3)						   BSD Library Functions Manual 					     PMC_ATTACH(3)

NAME

     pmc_attach, pmc_detach -- attaching and detaching process scope PMCs to target processes

LIBRARY

     Performance Counters Library (libpmc, -lpmc)

SYNOPSIS

     #include <pmc.h>

     int
     pmc_attach(pmc_id_t pmcid, pid_t pid);

     int
     pmc_detach(pmc_id_t pmcid, pid_t pid);

DESCRIPTION

     These functions control the set of target processes tracked by a process scope PMC.

     Function pmc_attach() is used to attach a process scope PMC specified by argument pmcid to a target process specified by argument pid.  Argu-
     ment pid may be zero to denote the current process.  If the PMC was allocated with modifier PMC_F_DESCENDANTS, the PMC will additionally
     attach to current and future descendents of the specified target process.	The PMC should be in a quiescent state (i.e., not running).

     Function pmc_detach() is used to detach a process scope PMC specified by argument pmcid from a process specified by argument pid.	Argument
     pid may be zero to denote the current process.

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 function pmc_attach() may fail with the following errors:

     [EBUSY]		Argument pmcid specified a PMC that was not in a quiescent state.

     [EBUSY]		The target process specified by function pmc_attach is being tracked by another process scope PMC that uses the same PMC
			hardware resources.

     [EEXIST]		The target process is already being tracked by the specified PMC.

     [EINVAL]		Argument pmcid specified a PMC with system scope.

     [EINVAL]		Argument pid specified an illegal process id.

     [EINVAL]		The current process does not own a PMC with the handle specified in argument pmcid.

     [EPERM]		The caller lacked the privilege needed to attach PMCs to the specified target process.

     [EPERM]		(i386 and amd64 architectures) The PMC specified by argument pmcid has been setup to allow the use of the RDPMC instruc-
			tion for self measurement.

     [ESRCH]		The current process does not own any PMCs.

     [ESRCH]		The process specified by argument pid did not exist.

     A call to function pmc_detach() may fail with the following errors:

     [EINVAL]		Argument pmcid specified a PMC with system scope.

     [EINVAL]		Argument pid specified an illegal process id.

     [EINVAL]		The current process does not own a PMC with the handle specified in argument pmcid.

     [EINVAL]		The specified PMC was not attached to the target process.

     [ESRCH]		The current process does not own any PMCs.

     [ESRCH]		The process specified by argument pid is not being monitored by hwpmc(4).

     [ESRCH]		The process specified by argument pid did not exist.

SEE ALSO

     pmc(3), pmc_start(3), pmc_stop(3), hwpmc(4)

BSD
								 November 25, 2007							       BSD