Return value of 'get_tuner_gain' if gain value is 0

[nocarryr]

The comments for rtlsdr_get_tuner_gain state that a return value of 0 is an error, but what would be an appropriate return value if the tuner gain is actually set to 0?

I have checked to see if this is a valid gain setting, and "0" is in the list of values returned by the 'get_tuner_gains' function with my RTL2832.

Could this possibly be a documentation issue, or does "0" definitely indicate an error?