change sox() returned type and success value

[mikeziminio]

changed docstring for sox() returned type and success value

[lostanlen]

Thanks! please add a unit test

[mikeziminio]

Thanks! please add a unit test

Vincent, thanks for the quick response!
I only changed the docstring, so I have no idea what tests can be added. Please advise me.

[lostanlen]

test that indeed sox returns an integer and that this integer is zero

[mikeziminio]

test that indeed sox returns an integer and that this integer is zero

ok, i will do it next week