[TAG] 2c tip: filtering in-place

[Ben Okopnik]

On Mon, Mar 22, 2004 at 11:21:52AM +0530, Kapil Hari Paranjape wrote:
> 
> As far reading and writing to pipes is concerned, here is how I
> understand it---please correct me if I am wrong. The kernel has its
> own *internal* settings on how much data is buffered before a writing
> process is put at the back of the queue and the reading process is woken
> up. Thus killing any one process in the "dd" pipeline could only result
> in *less* data being written than was read---an error from which one can
> recover as described above.

Since the source and the target file are the same, wouldn't you end up
with some truncated version of your data (i.e., the source being gone no
matter what)? It seems to me that the difference between complete
destruction of data and truncation of it at some random point can only
matter theoretically, except in a vanishingly small number of
situations.


* Ben Okopnik * okopnik.freeshell.org * Technical Editor, Linux Gazette *
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