.\" Copyright (c) 2007-2008 Joseph Koshy.  All rights reserved.
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.\" $FreeBSD$
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.Dd September 22, 2008
.Dt PMC_START 3
.Os
.Sh NAME
.Nm pmc_start ,
.Nm pmc_stop
.Nd start and stop a PMC
.Sh LIBRARY
.Lb libpmc
.Sh SYNOPSIS
.In pmc.h
.Ft int
.Fn pmc_start "pmc_id_t pmc"
.Ft int
.Fn pmc_stop "pmc_id_t pmc"
.Sh DESCRIPTION
These functions are used to start and stop a PMC.
.Pp
Function
.Fn pmc_start
starts the PMC specified by argument
.Fa pmc .
If the specified PMC has process scope and has not been attached
to any targets, it will be attached to the current process.
.Pp
Function
.Fn pmc_stop
stops the PMC specified by argument
.Fa pmc .
.Sh RETURN VALUES
.Rv -std
.Sh ERRORS
A call to these functions may fail with the following errors:
.Bl -tag -width Er
.It Bq Er EDOOFUS
Function
.Fn pmc_start
specified a PMC that requires a log file and no log file was
configured.
.It Bq Er EINVAL
The specified PMC is in the process of being deleted.
.It Bq Er EINVAL
Function
.Fn pmc_stop
specified a PMC that was never started.
.It Bq Er ENXIO
The specified PMC had system scope and its associated CPU was disabled or
absent.
.El
.Sh SEE ALSO
.Xr pmc 3 ,
.Xr hwpmc 4