On Apr 22, 2018, at 7:41 PM, Jed Brown <[email protected]> wrote:

"Smith, Barry F." <[email protected]> writes:

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Yuck, I think a far better user API is that PetscOptionsInsertFile() be callable before PetscInitialize(). The problem is that people have shoveled so much post-PetscInitialize() code into PetscOptionsInsertFile() over the years that stripping it all out would be painful. Maybe get a simplier pre- 2005 version of the routine and strip out the post-PetscInitialize() material?

You want every rank to open the file independently?

I forgot about that.

Or PetscOptionsInsertFile somehow caches the file contents without using PetscMalloc and broadcasts it after reaching PetscInitialize? That seems a bit crazy.

Maybe have use of pre-PetscInitialize() PetscOptionsInsertFile() cache the __file name(s)__ and then have PetscInitialize() loop over the cached filenames and load those options using simple MPI and PetscOptionsSetValue() before processing the command line etc Post-PetscInitialize() use of PetscOptionsInsertFile() would remain the same as today. We'd still need a stripped down version of PetscOptionsInsertFile(). Your proposed route allows bad decisions made years ago to dictate a bad user API forever. I don't like that. Barry

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Barry

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On Apr 22, 2018, at 5:54 PM, Jed Brown <[email protected]> wrote:

For users that read their own configuration files and/or choose PetscOptionsInsertFile after PetscInitialize, we don't have a good way to avoid overwriting PETSC_OPTIONS or command-line options. The user could manually find argv and the environment variable, but that's a poor abstraction. Should PetscOptionsInsertFile learn how to behave so as to add new entries to the options database, but not supersede any that already exist?