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PAPI_num_hwctrs

NAME

 PAPI_num_hwctrs - return the number of hardware counters on the cpu
 PAPI_num_cmp_hwctrs - return the number of hardware counters for the specified component

SYNOPSIS

C Interface

 #include <papi.h>
 int PAPI_num_hwctrs();
 int PAPI_num_cmp_hwctrs(int cidx);
 

Fortran Interface

 #include fpapi.h
 PAPIF_num_hwctrs(C_INT num)
 

DESCRIPTION

PAPI_num_hwctrs() returns the number of physical hardware counters present in the cpu. This is included to preserve backward compatability.

PAPI_num_cmp_hwctrs() returns the number of counters present in the specified component. By convention, component 0 is always the cpu. This count does not include any special purpose registers or other performance hardware. PAPI_library_init(3) must be called in order for this function to return anything greater than 0.

ARGUMENTS

cidx -- An integer identifier for a component. By convention, component 0 is always the cpu component.

RETURN VALUES

On success, this function returns a value greater than zero.

A zero result usually means the library has not been initialized.

EXAMPLES

 /* Query the cpu component for the number of counters. */
 printf("%d hardware counters found., PAPI_num_cmp_hwctrs(0));
 

BUGS

None.

SEE ALSO

PAPI_init_library(3), PAPI(3),PAPI_F(3)