gistfile1.cpp

#include <omp.h>
#include <stdio.h>

int num_threads, thread_id;

int main()
{
  #pragma omp threadprivate(thread_id)
  #pragma omp parallel
  {
    printf("%d: before!\n", thread_id);
    thread_id = omp_get_thread_num();
    printf("%d: Hello world!\n", thread_id);

    if(thread_id == 0)
    {
      num_threads = omp_get_num_threads();
      printf("Number of threads: %d\n", num_threads);
    }
  }

  return 0;
}