Hi, > > I'd like to add some better error messages to the snapscan backend. If I > > understand the current SANE standard correctly, the backend can supply an > > error string for a given status code by an implementation of > > sane_strstatus(). > > > > However, trying to implement sane_strstatus myself results in a linker > > error as all backends are linked against sane_strstatus.c by default. > > sane_strstatus is not a backend function, it is a function > that is linked to every library. You can not implement it > in your backend.
Fair enough. However, I believe that there should be a possibility for a backend to provide some detailed error message to a frontend. If this is not possible via sane_strstatus we should think of other ways for SANE-2. What I had in mind for my own implementation is an additional function set_error_descr(SANE_Status, SANE_String) which would be called from the backend prior to returning an error code. sane_strstatus would either return the string set by set_error_descr() if called with a matching SANE_Status or a default error string. Such an extension could also be built into the existing library function sane_strstatus without changing the interface. Regards, Oliver
