> > I note that when you copy a file to /floppy it seems to be incredibly > > quick. Is it in fact written to the floppy at the same time as it > > appears on /floppy ? > > > Ian, > > All I can say is "Ouch!". Unlike the DOS world, Unix in general, > and Linux in particular, do not guarantee that data will be written to > disk immediately after the in-memory copy of the disk blocks have been > updated. Unixes, in general, cache such info, and typically write out to > media (floppy disks, hard drives, etc) only when its efficient to do so. > Thus, when you make drastic changes to the contents of a floppy disk, the > in-memory copy of those disk blocks gets updated, and this happens quite > fast. However, unless this copy is written out to the floppy itself, the > changes will not be permanent. > > There is a standard way that Unixes support to force the write to > media. This is called the 'sync' command. If you had done 'sync' after > changing the contents of your floppy, you would have seen that your system > was writing to the floppy - which does take a significant amount of time. > Given the symptoms you describe, I would guess that you didnt do a 'sync' > before you popped the floppy disk, and thus your backups were never > written to floppy before you popped out the drive.
the Right Thing to do is umount the floppy before pushing the eject button. pietro.
