这是微软的一个查看USB设备枚举后状态的例程，虽然它只支持到USB1.1，但是对于想做USB sniffer的开发者来说很应该读一读。-This is a USB device enumeration View condition after the routines, although only to the USB 1.1 support, but wants to develop the USB sniffers are concerned, it should read.

RS-232C serial port monitor/sniffer in Win32 as a VS2008 ready to compile project.