Unmount USB Drive
 

I have a digital camera, i use Red Hat 9.0 and did the following commands:

ar root

mount -t auto /dev/sda1 /dog

you now have a filesystem: /dog/.......

you can copy to & from system as root

so before unmounting type:

syns;sync
when command prompt returns:
umount /dog

what am i doing wrong?

What makes you think you're doing something wrong? :)

According to the output, the USB camera was mounted at /dog. You should be able to read and write to the camera by accessing any file under /dog.

The message also says, you need to run two commands before you unmount the camera: syns and sync

Once those two commands finish, then you can unmount the camera by issuing umount /dog. The commands are there to guarantee that any information you write to the camera gets flushed out of the system before you unplug the USB connection.

Maybe another process is using this device, maybe your current directory is in the camera
so, try to return to your home directory and then umount