Ubuntu Manpages

PAPI_read

Read hardware counters from an event set.

C Interface:

#include <papi.h>
int PAPI_read(int EventSet, long_long * values );

PAPI_read() copies the counters of the indicated event set into the provided array.

The counters continue counting after the read.

Note the differences between PAPI_read() and PAPI_accum(), specifically that PAPI_accum() resets the values array to zero.

PAPI_read() assumes an initialized PAPI library and a properly added event set.

Parameters:

EventSet -- an integer handle for a PAPI Event Set as created by PAPI_create_eventset()
*values -- an array to hold the counter values of the counting events

Return values:

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 event set specified does not exist.

Examples

* do_100events();
* if (PAPI_read(EventSet, values) != PAPI_OK)
*    handle_error(1);
* // values[0] now equals 100
* do_100events();
* if (PAPI_accum(EventSet, values) != PAPI_OK)
*    handle_error(1);
* // values[0] now equals 200
* values[0] = -100;
* do_100events();
* if (PAPI_accum(EventSet, values) != PAPI_OK)
*     handle_error(1);
* // values[0] now equals 0 
*

See Also:

PAPI_accum

PAPI_start

PAPI_stop

PAPI_reset

Generated automatically by Doxygen for PAPI from the source code.