title: Difference between OMP_NUM_THREADS and OMP_THREAD_LIMIT
body: <p>What is the difference between these two OpenMP variables? In my understanding, OMP_THREAD_LIMIT sets an absolute cap on the number of simultaneously running threads that can be generated by the program as a whole, whereas OMP_NUM_THREADS specifies the number of threads that will be spawned in the next parallel construct. I have not been able to find a definitive answer to this.</p>
  
  <p>If this is true, then is there an OpenMP function that can set/get the value of OMP_THREAD_LIMIT within a C++ program (similar to omp_get_num_threads() for the OMP_NUM_THREADS) ?</p>
  
  <p>EDIT: I know the function omp_get_thread_limit() exists. omp_set_thread_limit() doesn't seem to exist. Is there a way to set the thread limit from within the program (during runtime)?</p>