On Tuesday 15 March 2005 21:37, Nuutti Kotivuori wrote:
> Nelson Castillo wrote:
> > Well, this is silly. If you use dd to truncate a file this way you
> > lose the trailing byte :)
> >
> > I really want to know : Is there another way to truncate a file in
> > Linux?
> >
> > This would be a silly way to avoid wasting a byte to truncate a file
> > to have 2 bytes with dd.
> >
> > ~$ echo 12345 > x
> > ~$ dd if=x skip=1 bs=1 count=1 > t
> > ~$ dd if=t seek=1 of=x count=1 bs=1
> > ~$ cat x
> > 12
> >
> > Regards,
> > Nelson.-
>
> I use trivial programs written in some other language to do the
> truncating. For example, python:
>
> file('xxx').truncate(10*1024*1024*1024)
>
> But do note that files created this way are sparse - and we have had
> *drastic* performance problems with files that are sparse.
Well, I've heard that sparse swap files are a big problem. In general, you
defer the space allocation, and I guess that depending on the filesystem this
can give problems.
> So I would recommend just writing zeros.
>
> -- Naked
--
Paolo Giarrusso, aka Blaisorblade
Linux registered user n. 292729
http://www.user-mode-linux.org/~blaisorblade
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