-isochronous endpoint I/O
-optional timerfd support (runtime detection)
-API docs
-notifications of hotplugged/unplugged devices
-thread safety
-signalfd emulation through pipes and sigaction() for older kernels
-signalfd not needed for usbfs? can we poll on the fd?
-use poll() rather than select()?
+Please see the libusb roadmap by visiting:
+https://github.com/libusb/libusb/milestones?direction=asc&sort=due_date&state=open