Hello I just encountered their manpages and it's a mess. I think in case of file I/O, a user should be deliberate about filename and other settings. Sometimes less is more and I think this is the case. Why anybody should use PETSC_VIEWER_BINARY_(comm) and then set the filename with environment variable? Better to use PetscObjectViewFromOptions for instance (PETSC_OPTIONS can be used if one wants to use env var).
(And BTW in case of HDF5, the option -viewer_hdf5_filename is not processed anywhere.) Any objections about removing these? Vaclav
