.TH "PAPI_start" 3 "Thu Dec 14 2023" "Version 7.1.0.0" "PAPI" \" -*- nroff -*-
.ad l
.nh
.SH NAME
PAPI_start \- Start counting hardware events in an event set\&.  

.SH SYNOPSIS
.br
.PP
.SH "Detailed Description"
.PP 

.PP
\fBC Interface:\fP
.RS 4
#include <\fBpapi\&.h\fP> 
.br
 int \fBPAPI_start( int  EventSet )\fP;
.RE
.PP
\fBParameters\fP
.RS 4
\fIEventSet\fP -- an integer handle for a PAPI event set as created by \fBPAPI_create_eventset\fP
.RE
.PP
\fBReturn values\fP
.RS 4
\fIPAPI_OK\fP 
.br
\fIPAPI_EINVAL\fP -- One or more of the arguments is invalid\&. 
.br
\fIPAPI_ESYS\fP -- A system or C library call failed inside PAPI, see the errno variable\&. 
.br
\fIPAPI_ENOEVST\fP -- The EventSet specified does not exist\&. 
.br
\fIPAPI_EISRUN\fP -- The EventSet is currently counting events\&. 
.br
\fIPAPI_ECNFLCT\fP -- The underlying counter hardware can not count this event and other events in the EventSet simultaneously\&. 
.br
\fIPAPI_ENOEVNT\fP -- The PAPI preset is not available on the underlying hardware\&.
.RE
.PP
\fBPAPI_start\fP starts counting all of the hardware events contained in the previously defined EventSet\&. All counters are implicitly set to zero before counting\&. Assumes an initialized PAPI library and a properly added event set\&.
.PP
\fBExample:\fP
.RS 4

.PP
.nf
int EventSet = PAPI_NULL;
long long values[2];
int ret;

ret = PAPI_create_eventset(&EventSet);
if (ret != PAPI_OK) handle_error(ret);

// Add Total Instructions Executed to our EventSet
ret = PAPI_add_event(EventSet, PAPI_TOT_INS);
if (ret != PAPI_OK) handle_error(ret);

// Start counting
ret = PAPI_start(EventSet);
if (ret != PAPI_OK) handle_error(ret);
poorly_tuned_function();
ret = PAPI_stop(EventSet, values);
if (ret != PAPI_OK) handle_error(ret);
printf("%lld\\\\n",values[0]);

.fi
.PP
.RE
.PP
\fBSee also\fP
.RS 4
\fBPAPI_create_eventset\fP \fBPAPI_add_event\fP \fBPAPI_stop\fP 
.RE
.PP


.SH "Author"
.PP 
Generated automatically by Doxygen for PAPI from the source code\&.