[nzlug] Completely unmounting USB device

[Cliff Pratt]

Robin Sheat wrote:
> I have an MP3 player that charges on USB. When you first connect it, the 
> computer recognises it and talks to it, and all is well. However, I want to 
> know how much it is charged. According to the manual, you can do this in 
> windows by using the 'safely remove hardware' thing. In Linux, unmounting it 
> removes the mountpoint, but it doesn't seem to remove the device node.
> 
> How can I tell Linux to completely stop talking to a USB device so it'll show 
> me the amount that it's charged?
> 
> I note that my camera seems to be able to do this[0], when I unmount it, the 
> colour of the light changes, but it seems to be using a different method of 
> detecting than this MP3 player.
> 
> Robin.
> 
> [0] at least, up until I lost the USB cable in Australia. Fortunately, feisty 
> now works with the SD card reader on my laptop.
> 
Hmm, most camera I've seen use a standard USB cable.

Cheers,

Cliff