Currently it only has the writeAnalog (analogWrite) function, but the pigpio API
has lots more:
getPwmDutyCycle(), pwmRange(range), getPwmRange(), getPwmRealRange(), pwmFrequency(frequency), getPwmFrequency()
I think that these should only be used for initialisation stuff. The only function that should be exposed is writeAnalog (maybe change to simply "write").