USB Devices not working

[Shawn Iverson]

> From: Shawn Iverson [mailto:shawn at nccsc.k12.in.us]
> Sent: Monday, February 02, 2004 7:20 PM
> 
> > From: Fritz Whittington [mailto:f.whittington at att.net]
> > Sent: Sunday, February 01, 2004 10:46 AM
> > 
> > 
> > >> Also, once you are have troubleshooted your issue, 
> always manually 
> > >> unmount
> > >> your device before unplugging it, especially if you are 
> > performing write
> > >> operations to it.
> > >>
> > How very important!   If you don't believe that delayed-write is 
> > working, try mounting a USB fs (one that uses a solid-state 
> > memory, like 
> > Compact Flash or Smart Media),  copying several MB of files 
> > from it to a 
> > hdd, and note how slow it is.   Then delete all the files 
> on the USB 
> > device, and copy all the files back.  The copy is done almost in an 
> > instant!  But then, when you unmount it, you can see it 
> take several 
> > seconds to actually write the files from cache.  So if you 
> > yanked it out 
> > without unmounting it, you wouldn't really have anything.
> > 
> 
> It would be nice if usb devices such as this could be forced 
> to write their
> data ASAP instead of waiting for a umount (despite a 
> performance lag).  It
> is so tempting for many people that I know to just go ahead 
> and unplug.  I
> am going to do some research on this.
> 
> 

The closest thing I could find was the "sync" option that can be passed to
mount.  Taking the device entry out of updfstab and manually making an fstab
entry seems to be the best way to pass the sync option.  This works for the
msdos and vfat filesystems.  It still is necessary to wait before unplugging
the device, just not as long.