# PETSC_MPI_THREAD_REQUIRED
the required threading support used if PETSc initializes MPI with `MPI_Init_thread()`. 


## Notes
By default `PETSC_MPI_THREAD_REQUIRED` equals `MPI_THREAD_FUNNELED`.


## See Also
 `PetscInitialize()`


## Level
beginner

## Location
<A HREF="PETSC_DOC_OUT_ROOT_PLACEHOLDER/include/petscsys.h.html#PETSC_MPI_THREAD_REQUIRED">include/petscsys.h</A>


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