[MPICH] standard input limited to 4096 bytes?

[Martin Kleinschmidt]

Hi,

I'm having problems with standard input.

the following program:

      program  test
      
      include 'mpif.h'
      integer myid, nproc

      write(*,*) '0'
      call MPI_init(MPIerr)
      write(*,*) '0a'
      call MPI_comm_rank(MPI_comm_world,myid, MPIerr)
      write(*,*) '0b'
      call MPI_comm_size(MPI_comm_world,nproc,MPIerr)
      write(*,*) '0c'

      end

runs correctly when started with
mpiexec -n2 ./a.out < input_file_smaller_than_4097_bytes

but hangs in call MPI_init when called with
mpiexec -n2 ./a.out < input_file_larger_than_4096_bytes

note that the program does NOT access standard input!

I'm using mpich2-1.0.4p1, intel compilers 9.x, fedora core2.

Is this a general problem of mpich? 
Is there any solution?
In my "real" program, I regularly need standard input from files larger
than 4096 bytes.


thanks!

   ...martin