"Haben Sie etwas zum Schreiben?" in a phone-call context means:
a) Would you like to leave a note?
b) Do you have something close at hand to write down a note?
c) something else (idiomatic expression)
The question popped up during an exercise and we are doubtful about the real meaning because of the following reasons:
- have to can be used in replacement of must (müssen)
- Schreiben has multiple meanings
- some idiomatic expression sometimes can't be found on a dictionary.