Disable File System Cache for USB Devices? Possible Duplicate:
  Disable &ldquo;the disk was not ejected properly&rdquo; message  




When I have a USB Device like a SD Card, USB Drive or external hard drive, I always need to unmount it, otherwise OS X complains about the device not being ejected properly.

On Windows, the solution to this is trivial: Disable the File System Cache for USB Drives, so that they can be immediately and safely removed.

Does OS X have a way to disable the cache?
On SuperUser Q&amp;A another user asked a similar question. The solution is a little bit tricky/efforty:

This should be possible by manually mounting the drive via the terminal. You'll have to eject the drive when you plug it in and then remount it in the terminal using the noasync option.
The best way to go about this would be to run mount in the terminal and take down the device so you know what to remount. Then umount /dev/disk1s1 (where disk1s1 is the device name) then mount -o noasync /dev/disk1s1. This method would also apply to most linux distros.
As you can see, it's easier to just remember to eject.