Differences between "df -m" and summarized "du -sm *" in FC4

[Roberto Ragusa]

Paul Howarth wrote:

> Deleting an open temp file is a fairly common technique - it prevents
> other processes getting any access to the file.

Vmware does that with really big files (they are the RAM of the
virtual machines).

You can detect such files with a simple
  lsof -n|grep deleted|grep /tmp

Another confusing situation can happen when you use a
not-empty directory as mount point. The content of the
dir becomes almost invisible (including "du -sm") so
you don't realize you have a lot of stuff on the disk.

I don't think Joachim has mounted something inside /tmp,
but knowing about this effect could be useful for someone
reading the list.

Best regards.
-- 
   Roberto Ragusa    mail at robertoragusa.it