Rsync shouldn't display a meaningless speedup on a dry run

foner-rsync at foner-rsync at
Wed Nov 7 03:22:56 GMT 2007

    > Date: Mon, 05 Nov 2007 13:17:32 -0500
    > From: Matt McCutchen <matt at>

    > I think rsync should omit the speedup on a dry run.  The attached patch
    > makes it do so.

I worry about those trying to write things that parse rsync's output;
if -n changes the output format, such things will have to be tested on
live data.

Is it possible (e.g., without ridiculous amounts of code-massaging) to
have -n output the speedup (or some more-reasonable estimate) anyway?
Sure, all kinds of differences haven't been computed, but...  Or maybe
just have it report a speedup of 1.00 instead?  Still misleading, but
it preserves the output format and is trivial to write (but still,
alas, confusing for the user, so this doesn't fill me with glee).

Or we can just assume that such parsers might be looking at the file
list, but it's dubious that applications exist that care about the
speedup data and hence would be throwing away such lines anyway (and
would not break if it doesn't appear).

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