I am trying to send a single integer from one process to another. However, I am getting a segmentation fault/invalid memory reference. Apparently I have misunderstood some basic notion of MPI. Can anyone tell me what I am doing wrong?
program read_data
use mpi
implicit none
integer :: ierr, my_id, max_id, test
call MPI_INIT(ierr)
call MPI_COMM_RANK(MPI_COMM_WORLD, my_id, ierr)
call MPI_Comm_size(MPI_COMM_WORLD, max_id, ierr)
if (my_id .eq. 0) then
test = 1
call MPI_Send(test, 1, MPI_Integer, 1, 6, MPI_COMM_WORLD, ierr)
endif
if (my_id .eq. 1) then
call MPI_Recv(test, 1, MPI_Integer, 0, 6, MPI_COMM_WORLD, ierr)
write(*,*) test
endif
call MPI_FINALIZE(ierr)
end program read_data
You lack the status array argument in MPI_Recv. See the manual
MPI_RECV(BUF, COUNT, DATATYPE, SOURCE, TAG, COMM, STATUS, IERROR)