Uncle George wrote: > Robert Hancock wrote: >> It's because you haven't done anything to handle the error which is > still persisting. Likely the only thing sane you can do in this case > is close the fd and try to reopen it later. >> > This seems to be true, but not for what you might think. > > It appears that if u plug the USB/serial device back into the usb-hub, > the code creates a /dev/ttyUSB1 ( if you have not yet closed the > disconnected /dev/ttyUSB0. ) When you do close /dev/ttyUSB0, then the > device is erased from the /dev directory. > > Now /dev/ttyUSB1 is the device. And /dev/ttyUSB0 disappeared. This > does not seem proper. As now the program has no idea or capability to > re-open the GPS device.
Sure it does. The days of programs being able to blindly assume static device names are gone. Hotplug is upon us and it necessitates a different way of thinking, even in userspace. Apps need to be smart enough to re-enumerate compatible devices and pick one. Even if the kernel were to maintain the illusion of a static device name in the simple case, the app still needs smarts to handle the general case. And I say this as the maintainer of an app that is going thru exactly this evolution. It's painful, but necessary. --Adam ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ linux-usb-devel@lists.sourceforge.net To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-devel
