program mpi_io_hint
      implicit none
      include "mpif.h"

      integer rank, info, err, fp, cmode, mpistatus
      integer buf(10)

      call MPI_Init(err)
      call MPI_Comm_rank(MPI_COMM_WORLD, rank, err)

      ! create and set MPI-IO hint, romio_no_indep_rw
      call MPI_Info_create(info, err)
      call check(err, "MPI_Info_create")
      call MPI_Info_set(info, 'romio_no_indep_rw', 'true', err)
      call check(err, "MPI_Info_set")

      ! create file
      cmode = IOR(MPI_MODE_RDWR, MPI_MODE_CREATE)
      call MPI_File_open(MPI_COMM_WORLD, 'testfile', cmode,
     +                   info, fp, err)
      call check(err, "MPI_File_open")

      ! free the info object
      call MPI_Info_free(info, err)
      call check(err, "MPI_Info_free")

      ! Only root writes to the file using independent call
      if (rank .EQ. 0) then
          call MPI_File_write(fp, buf, 10, MPI_INTEGER, mpistatus, err)
          call check(err, "MPI_File_write")
      endif

      call MPI_File_close(fp, err)
      call check(err, "MPI_File_close")

      call MPI_Finalize(err)
      end

      subroutine check(err, func)
          implicit none
          include "mpif.h"
          integer err
          character func*(*)

          ! local variables
          integer ierr, err_len, errorclass
          character(LEN=MPI_MAX_ERROR_STRING) err_string

          if (err .NE. MPI_SUCCESS) then
              call MPI_Error_class(err, errorclass, ierr)
              call MPI_Error_string(err, err_string, err_len, ierr)
              print*,'Error at ', trim(func),' ',trim(err_string)
          endif
      end ! subroutine check