/*D
   MPI_Initialized - Indicates whether 'MPI_Init' has been called.

Synopsis:
.vb
int MPI_Initialized(int *flag)
.ve

Output Parameters:
. flag - Flag is true if MPI_INIT has been called and false otherwise (logical)

.N ThreadSafe

.N Fortran

.N Errors
.N MPI_SUCCESS
.N MPI_ERR_ARG
.N MPI_ERR_OTHER

D*/

