I have added the flag both as a dsvdc_new argument and as a command line option to the reference example.
IMPORTANT: This change modifies the dsvdc.h API in a non-backwards-compatible way, i.e, existing code using dsvdc.h will not compile after this change. More specifically, the signature of the dsvdc_new function has changed.
If this is not acceptable, I can crate revert the dsvdc_new function change, and add an additional, alternative, initialization function to the API. I would suggest a new initialization function that takes a configuration object as an argument, so future changes of this kind may be backwards compatible.