Contents
using_threads - In a parallel environment, if called from a
serial region of the master thread it returns the number of
threads available for execution (determined by function
OMP_GET_NUM_THREADS). Else, if it is called from a thread
in the team executing the parallel region it returns a 1.
USING_THREADS subroutine
INTEGER FUNCTION USING_THREADS()
INTEGER*8 FUNCTION USING_THREADS_64()
F95 INTERFACE
INTEGER FUNCTION USING_THREADS()
INTEGER(8) FUNCTION USING_THREADS_64()
C INTERFACE
#include <sunperf.h>
int using_threads();
long using_threads_64();
In a parallel environment, if called from a serial region of
the master thread USING_THREADS returns the number of
threads available for execution. This number is determined
by function call OMP_GET_NUM_THREADS (See the specifications
for the OpenMP Fortran Application Program Interface at
http://www.openmp.org for more details on
OMP_GET_NUM_THREADS). Else, if it is called from a thread
in the team executing the parallel region, it returns a 1.
A user routine can call using_threads to determine if it is
already in a parallel region. If this is the case, a 1 is
returned and the routine can choose the serial path instead
of going parallel, thus avoiding nested parallellism.