acc_async_test_all– Tests for completion of all asynchronous operations.
This function tests for completion of all asynchrounous operations.
In C/C++, a non-zero value will be returned to indicate all asynchronous
operations have completed. While Fortran will return a
any asynchronous operation has not completed, C/C++ returns a zero and
Fortran returns a
OpenACC specification v2.0, section 3.2.7.