1 isochronous endpoint I/O
2 optional timerfd support (runtime detection)
4 notifications of hotplugged/unplugged devices
6 signalfd emulation through pipes and sigaction() for older kernels
7 signalfd not needed for usbfs? can we poll on the fd?
8 use poll() rather than select()?
9 abstraction for cross-platform-ness
11 API style/naming points to reconsider
12 =====================================
14 struct libusb_(bulk|control)_transfer or parameters?
16 urbh in general (should this be a transfer handle?)
18 config struct/function naming