Usage Tips

• When using ROMIO with SGI MPI, you may sometimes get an error message from SGI MPI: ``MPI has run out of internal datatype entries. Please set the environment variable MPI_TYPE_MAX for additional space.'' If you get this error message, add the following line to your .cshrc file:
  setenv MPI_TYPE_MAX 65536
  Use a larger number if you still get the error message.
• If a Fortran program uses a file handle created using ROMIO's C interface, or vice versa, you must use the functions MPI_File_c2f or MPI_File_f2c (see § 4.12.4 in [4]). Such a situation occurs, for example, if a Fortran program uses an I/O library written in C with MPI-IO calls. Similar functions MPIO_Request_f2c and MPIO_Request_c2f are also provided.
• For Fortran programs on the Intel Paragon, you may need to provide the complete path to mpif.h in the include statement, e.g.,
  include '/usr/local/mpich/include/mpif.h'
  instead of
  include 'mpif.h'
  This is because the -I option to the Paragon Fortran compiler if77 doesn't work correctly. It always looks in the default directories first and, therefore, picks up Intel's mpif.h, which is actually the mpif.h of an older version of MPICH.