3.1.6 omp_in_parallel Function

The omp_in_parallel function returns a nonzero value if it is called within the dynamic extent of a parallel region executing in parallel; otherwise, it returns 0. The format is as follows:

#include <omp.h>
int omp_in_parallel(void);

This function returns a nonzero value when called from within a region executing in parallel, including nested regions that are serialized.