"Smith, Barry F." <bsm...@mcs.anl.gov> writes: >> There is some nontrivial infrastructure that would be needed for this >> model. >> >> 1. This new component needs to be built into a new library such as >> libpetsc-plugin.a (when static). >> >> 2. Users need to know when they should link this module. They'll need a >> link line something like -lpetsc-plugin -lslepc -lpetsc in this case. >> It would need to be specified correctly in makefiles and pkg-config. >> >> 3. Anything with __attribute__((constructor)) runs *before* main, thus >> before PetscInitialize. There would need to be a new mechanism to >> register a callback to be run at the end of PetscInitialize. > > Are you saying we need something like PetscPlugInRegister(PetscErrorCode > (*)(void)) that can be called before PetscInitialize() by plugin libraries > that > registers the function that PetscInitialize() than calls? This is doable, > just needs to use malloc() directly and cannot use PETSc's FList constructs.
Yes, either with malloc or some fixed (fairly large) number of slots. If using malloc, you'd want an __attribute__((destructor)) that runs after main to free the list. (You can't free it in PetscFinalize because the user could call PetscInitialize again; you need to free it to avoid Valgrind noise.)
