file size different from ls to du

[Bruce Cran]

On Tue, Jul 29, 2003 at 05:27:14PM +0200, Bogdan TARU wrote:
> 
> 	Hi Drew,
> 
>  I have tried to create some files of myself, with 'spaces' in them
> (holes?), but they don't act like this. So could you please explain what
> 'sparse' means, and the 'trick' to create them?
> 

Try using the 'truncate' utility:

truncate -s 102400G onehundred_terabytes

This will create a file which looks like it's 100TB though 'ls', but
which only uses 64KB in the directory usage via 'du'.  Generally, creating
a file, seeking past the end of the file then writing something, 
will create a 'sparse' file.  This, when read, will appear 
to contain zeros for all entries past the previous end of file, 
to the entry which was written to.

--
Bruce Cran