[LAD] [OT] bash vs disk activity

Hi, Does anyone here have a bash script that will monitor disk activity or accurately provide a progress bar of a simple file copy? I have a script that transfers data to a usb device using cp -a /xxx /usb_device & But it falls over with reporting back the actual amount of data that has been transferred. It seems that the copy command doesn't return the actual amount transferred to disk but more the amount it has queued to transfer. For example if I transfer 200mb to a usb disk the copy command takes about 30 seconds before it returns and the data takes about 5 minutes before it is actually finished being transferred and the device is unmountable. How would I track the 5 minutes of data transfer with bash? Cheers. -- Patrick Shirkey Boost Hardware Ltd.