Using OpenMPI 1.0.1 compiled with g95 on OS X (same problem on Debian
Linux with g95, I have not tested other compilers yet)
mpif90 spawn.f90 -o spawn
In file spawn.f90:35
MPI_COMM_WORLD, slavecomm, MPI_ERRCODES_IGNORE, ierr )
1
Error: Generic subroutine 'mpi_comm_spawn' at (1) is not consistent
with a specific subroutine interface
make: *** [spawn] Error 1
I can't see the problem with the following, all the arguments match
the info presented in the book "Using MPI-2" page 236:
call MPI_Comm_spawn('subprocess', MPI_ARGV_NULL, universe_size-1,
MPI_INFO_NULL, 0, &
MPI_COMM_WORLD, slavecomm, MPI_ERRCODES_IGNORE, ierr )
the entire test program follows:
program main
USE MPI
implicit none
integer :: ierr,size,rank,slavecomm
integer (kind=MPI_ADDRESS_KIND) :: universe_size
integer :: status(MPI_STATUS_SIZE)
logical :: flag
integer :: ans
integer :: k
call MPI_INIT(ierr)
call MPI_COMM_RANK(MPI_COMM_WORLD,rank,ierr)
call MPI_COMM_SIZE(MPI_COMM_WORLD,size,ierr)
if ( size /= 1 ) then
if ( rank == 0 ) then
write(*,*) 'Only one master process permitted'
write(*,*) 'Terminating all but root process'
else
call MPI_FINALIZE(ierr)
stop
end if
end if
call MPI_Comm_get_attr(MPI_COMM_WORLD, MPI_UNIVERSE_SIZE,
universe_size, flag,ierr)
if ( .not. flag ) then
write(*,*) 'This MPI does not support UNIVERSE_SIZE.'
write(*,*) 'How many processes total?'
read(*,*) universe_size
else if ( universe_size < 2 ) then
write(*,*) 'How many processes total?'
read(*,*) universe_size
end if
call MPI_Comm_spawn('subprocess', MPI_ARGV_NULL, universe_size-1,
MPI_INFO_NULL, 0, &
MPI_COMM_WORLD, slavecomm, MPI_ERRCODES_IGNORE, ierr )
do k = 1, universe_size-1
write(*,*) 'master receiving'
call MPI_RECV( ans, 1, MPI_INTEGER, MPI_ANY_SOURCE, MPI_ANY_TAG,
slavecomm, status, ierr )
write(*,*) 'answer=',ans,' from alpha',k
end do
call MPI_COMM_FREE(slavecomm,ierr)
call MPI_FINALIZE(ierr)
end