papi_start_counters(3) [centos man page]

PAPI_start_counters(3)						       PAPI						    PAPI_start_counters(3)

NAME

       PAPI_start_counters -

       Start counting hardware events.

SYNOPSIS

Detailed Description
       @par C Interface:
       int PAPI_start_counters( int *events, int array_len );

       Parameters:
	   *events an array of codes for events such as PAPI_INT_INS or a native event code
	   array_len the number of items in the *events array

       Return values:
	   PAPI_EINVAL One or more of the arguments is invalid.
	   PAPI_EISRUN Counters have already been started, you must call PAPI_stop_counters() before you call this function again.
	   PAPI_ESYS A system or C library call failed inside PAPI, see the errno variable.
	   PAPI_ENOMEM Insufficient memory to complete the operation.
	   PAPI_ECNFLCT The underlying counter hardware cannot count this event and other events in the EventSet simultaneously.
	   PAPI_ENOEVNT The PAPI preset is not available on the underlying hardware.

       PAPI_start_counters() starts counting the events named in the *events array. This function cannot be called if the counters have already
       been started. The user must call PAPI_stop_counters() to stop the events explicitly if he/she wants to call this function again. It is the
       user's responsibility to choose events that can be counted simultaneously by reading the vendor's documentation. The length of the *events
       array should be no longer than the value returned by PAPI_num_counters().

       if( PAPI_start_counters( Events, num_hwcntrs ) != PAPI_OK )
	   handle_error(1);
	*

       See Also:
	   PAPI_stop_counters() PAPI_add_event() PAPI_create_eventset()

Author
       Generated automatically by Doxygen for PAPI from the source code.

Version 5.2.0.0 						  Tue Jun 17 2014					    PAPI_start_counters(3)

PAPI_start(3)							       PAPI							     PAPI_start(3)

NAME

       PAPI_start -

       Start counting hardware events in an event set.

SYNOPSIS

Detailed Description
       C Interface:
	   #include <papi.h>
	    int PAPI_start( int  EventSet );

       Parameters:
	   EventSet -- an integer handle for a PAPI event set as created by PAPI_create_eventset

       Return values:
	   PAPI_OK
	   PAPI_EINVAL -- One or more of the arguments is invalid.
	   PAPI_ESYS -- A system or C library call failed inside PAPI, see the errno variable.
	   PAPI_ENOEVST -- The EventSet specified does not exist.
	   PAPI_EISRUN -- The EventSet is currently counting events.
	   PAPI_ECNFLCT -- The underlying counter hardware can not count this event and other events in the EventSet simultaneously.
	   PAPI_ENOEVNT -- The PAPI preset is not available on the underlying hardware.

       PAPI_start 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.

       Example:

	   *  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
",values[0]);
	   *

       See Also:
	   PAPI_create_eventset PAPI_add_event PAPI_stop

Author
       Generated automatically by Doxygen for PAPI from the source code.

Version 5.2.0.0 						  Tue Jun 17 2014						     PAPI_start(3)