include 'mpif.h'


INTEGER IERR,MYRANK,lop,test,request
character(len=10)  mpireqmax

integer status(MPI_STATUS_SIZE)

CALL getenv('MPI_REQUEST_MAX',mpireqmax)

write(6,*) 'MPI_REQUEST_MAX=',mpireqmax


CALL sleep(2)

CALL mpi_init(ierr)


CALL MPI_COMM_RANK(MPI_COMM_WORLD,MYRANK,IERR)

IF (MYRANK.EQ.0) THEN

  lop = 0

  DO WHILE(.TRUE.)

    lop = lop + 1

    CALL MPI_Isend(test,1,MPI_INTEGER,1,0,MPI_COMM_WORLD,request,IERR)
!    CALL MPI_WAIT(request,status,ierr)
    
    write(6,fmt='(I6)',ADVANCE='NO') lop

    if(mod(lop,20).eq.0) write(6,*)

  END DO

END IF

IF (MYRANK.EQ.1) THEN

  lop = 0

  DO WHILE(.TRUE.)

    lop = lop + 1

    CALL MPI_RECV(test,1,MPI_INTEGER,0,0,MPI_COMM_WORLD,status,IERR)

  END DO

END IF



CALL MPI_BARRIER(MPI_COMM_WORLD,ierr)
write(6,*) 'past barrier'
call flush(6)

CALL MPI_FINALIZE(MPI_COMM_WORLD,ierr)


END