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Re: [vox-tech] files with holes in them
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Re: [vox-tech] files with holes in them

On Fri, Nov 17, 2000 at 08:50:21PM -0800, Peter Jay Salzman wrote:
> i'm not sure i follow.
> so du -k returns allocated disk space in kilobyte blocks.


> 10000.003 kb of data can't fit in 24 kb of allocated disk space.  what am
> i missing?

ext2fs (and other unix file systems) support "sparse files", that is,
files with long runs of nulls in them.  man tar (or cp) and search for 
"sparse", you'll see there are options for recognizing and handling sparse

> if anything, i'd expect st_blocks (in kb) >= st_size (in kb).

dunno on this one.

ls is the inode's recorded filesize.  du is the inode's physically allocated 
block count.

You can create a gigabyte long file if you like... using only 1 block on
disk.  (open(...O_CREAT); lseek(0,1024*1024*1024); write (...))  (haven't
done this in years, might be wrong).

Ted Deppner

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