Re: file size different from ls to du

From: Bruce Cran (bruce_at_cran.org.uk)
Date: 07/29/03

  • Next message: Harti Brandt: "Re: file size different from ls to du" 
    Date: Tue, 29 Jul 2003 17:02:15 +0100
To: Bogdan TARU <bgd@icomag.de>

    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
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  • Next message: Harti Brandt: "Re: file size different from ls to du"