Yes, it works. So to suppress the .info file, I either replace
PetscViewerBinaryOpen(comm, fn, FILE_MODE_WRITE, &viewer); with PetscViewerCreate(comm, &viewer); PetscViewerSetType(viewer,PETSC_VIEWER_BINARY); PetscViewerBinarySkipInfo(viewer); PetscViewerFileSetMode(viewer, FILE_MODE_WRITE); PetscViewerFileSetName(viewer,fn); in my code, or use "-viewer_binary_skip_info" at run time. Thanks. Shao-Ching Barry Smith wrote: > > From the manual page > > /*@ > PetscViewerBinarySkipInfo - Binary file will not have .info file > created with it > > Not Collective > > Input Paramter: > . viewer - PetscViewer context, obtained from PetscViewerCreate() > > Options Database Key: > . -viewer_binary_skip_info > > Level: advanced > > Notes: This must be called after PetscViewerSetType() but before > PetscViewerFileSetName(). If you use PetscViewerBinaryOpen() then > you can only skip the info file with the -viewer_binary_skip_info > flag. To use the function you must open the > viewer with PetscViewerCreate(), PetscViewerSetType(), > PetscViewerFileSetName(). > > The .info contains meta information about the data in the binary > file, for example the block size if it was > set for a vector or matrix. > > Concepts: PetscViewerBinary^accessing info file > > .seealso: PetscViewerBinaryOpen(), PetscViewerBinaryGetDescriptor(), > PetscViewerBinarySetSkipOptions(), > PetscViewerBinaryGetSkipOptions() > @*/ > > On Feb 6, 2009, at 6:27 PM, Shao-Ching Huang wrote: > >> Hi >> >> I am getting a zero-sized file "foo.info" when I write a vector, say >> "my_vec", to disk file "foo": >> >> MPI_Comm comm; >> PetscViewer viewer; >> Vec my_vec; >> ... >> PetscViewerBinaryOpen(comm, "foo", FILE_MODE_WRITE, &viewer); >> VecView(my_vec, viewer); >> PetscViewerDestroy(viewer); >> >> My questions are: >> 1. Can I safely ignore the .info file? (Is it useful?) >> 2. How can I prevent the .info file from being generated? >> >> Thanks, >> >> Shao-Ching >> >> >> Matthew Knepley wrote: >>> On Thu, Feb 5, 2009 at 7:48 PM, Shao-Ching Huang >>> <schuang at ats.ucla.edu> wrote: >>>> Hi, >>>> >>>> I am trying to create restart/check-pointing files for a time-stepping >>>> simulation (by writing out vectors to files). >>>> >>>> 1. Does VecView always use the MPI collective I/O? >>>> >>>> The HTML documentation of PetscViewerBinaryOpen says: "For writing >>>> files it only opens the file on processor 0 in the communicator." >>> You must run with -viewer_binary_mpiio. However, I recommend very very >>> strongly that you profile this first. We have not need to use MPI/IO >>> below >>> several thousand processors. >>>> 2. Do I have to set anything to enable MPI I/O when configuring PETSc? >>>> (My MPI library has MPI I/O.) >>> This should happen automatically. >>> Matt >>>> Thank you. >>>> >>>> Shao-Ching >
