-extern void PWM_Set(int pin, bool polarity, long period, long duty); // period and duty are in ns
-extern void PWM_Stop(int pin);
-#else
-//Empty defines so it compiles on any platform that's not the BBB
-#define GPIO_Export(pin)
-#define GPIO_Unexport(pin)
+extern bool PWM_Set(int pin, bool polarity, long period, long duty); // period and duty are in ns
+extern bool PWM_Stop(int pin);