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Updated: June 2017
 
 

using_threads (3p)

Name

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

Synopsis

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();

Description

Oracle Solaris Studio Performance Library                    using_threads(3P)



NAME
       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


SYNOPSIS
       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();



PURPOSE
       In a parallel environment, if called from a serial region of the master
       thread USING_THREADS returns the number of threads available for execu-
       tion.   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.



                                  7 Nov 2015                 using_threads(3P)