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Date: Tue, 26 Apr 2011 13:06:01 -0400
From: JimR <NotReallyMyEmail@example.net>
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Subject: File real location
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This applies to Unix as well as Linux, but has been bugging me for awhile.

Supposed I have a filesystem that is optionally mounted.  Let's says the 
mount point is
/foo

Now I create a file on it, let's call it bar.  Now I have
/foo/bar

In an alternative case, the filesystem is not mounted.  I can still 
create a file bar in the directory foo, but it will fall onto the 
default filesystem (likely root filesystem).

How can I tell the difference between these 2 files, i.e., on which 
filesystem did the file land?

Thanks,
JimR