#include "petscsys.h" PetscErrorCode PetscOptionsPrefixPush(PetscOptions options,const char prefix[])Not Collective, but prefix will only be applied on calling ranks
| options | - options database, or NULL for the default global database | |
| prefix | - The string to append to the existing prefix |
| -prefix_push <some_prefix_> | - push the given prefix | |
| -prefix_pop | - pop the last prefix |
-prefix_push system1_ -options_file system1rc -prefix_pop -prefix_push system2_ -options_file system2rc -prefix_pop
where the files no longer require all options to be prefixed with -system2_.