Get the number of hardware counters available on the system. More...

Detailed Description

C Interface:: #include <papi.h>
int PAPI_num_counters( void );

Postcondition: Initializes the library to PAPI_HIGH_LEVEL_INITED if necessary.

Return values

PAPI_EINVAL	papi.h is different from the version used to compile the PAPI library.
PAPI_ENOMEM	Insufficient memory to complete the operation.
PAPI_ESYS	A system or C library call failed inside PAPI, see the errno variable.

Examples:: int num_hwcntrs;
// The installation does not support PAPI
if ((num_hwcntrs = PAPI_num_counters()) < 0 )
handle_error(1);
// The installation supports PAPI, but has no counters
if ((num_hwcntrs = PAPI_num_counters()) == 0 )
fprintf(stderr,"Info:: This machine does not provide hardware counters.\n");

PAPI_num_counters() returns the optimal length of the values array for the high level functions. This value corresponds to the number of hardware counters supported by the current CPU component.

Note: This function only works for the CPU component. To determine the number of counters on another component, use the low level PAPI_num_cmp_hwctrs().

The documentation for this class was generated from the following file:

papi_hl.c