On 2010-01-16, Milo Luo <lxybhbh / gmail.com> wrote:
> I meant without string or tmp file, write to original file.

In general, on most systems, the only modifications you can make without
a temporary file or something comparable are those which do not change the
number of characters in a file.  You can't insert or delete characters in
the middle of a file.

-s
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