[petsc-dev] PetscInitialize in Fortran

[Barry Smith]

   Is your question, why is there a 

PETSC_EXTERN void PETSC_STDCALL petscinitialize_(CHAR filename PETSC_MIXED_LEN(len),PetscErrorCode *ierr PETSC_END_LEN(len))
{
#if defined (PETSC_USE_NARGS)
  short       flg,i;
#else
  int         i;
#if !defined(PETSC_HAVE_PXFGETARG_NEW) && !defined (PETSC_HAVE_PXFGETARG_NEW)
  int         j;
#endif
#endif

function in zstart.c that has a great deal of code duplication (yuck) with the C PetscInitialize() function? 

The reason is because a long long long time ago we had great difficulty using the exact same code for most of the initialization in C and Fortran for a bunch of subtle and machine specific reasons I forgot (Satish may remember). We introduced the code duplication and have had no problems since (except sometimes forgetting to put new things added to PetscInitialize() into petscinitialize_() !)    Yes ideally we would eliminate the code duplication with a refactorization but the gain would mostly be a good feeling and since Satish and I sweated a lot of tears long ago with crazy stuff that went wrong until we duplicated code I would vote against trying to put them together.

If your question is something else then please restate your question.

   Barry



On Oct 29, 2013, at 4:03 PM, Matthew Knepley <knepley at gmail.com> wrote:

> Why do we have a copy of PetscInitialize() in zstart.c? We just call PetscFinalize()
> from there.
> 
>    Matt
> 
> -- 
> What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead.
> -- Norbert Wiener