duplicated file removal: call for comment

[Wayne Davison]

On Tue, Feb 11, 2003 at 11:17:36PM -0800, Craig Barratt wrote:
> I suspect (but haven't checked) that if a 2.5.5 receiver is talking to
> a 2.5.6 sender then 2.5.5 will send the index for the 3rd file, which
> will be null_file on 2.5.6.

Yikes, I think you're right.  I think 2.5.6 should be changed so that
the sender never removes any duplicate names from the sorted list -- we
let the receiver handle this (since it is the receiver that drives what
files to process) and thus the sending side will always have a non-NULL
name available for whatever file the receiver requests.  This will
ensure that 2.5.6 will also work right with an old 1.6.9 client that
used to remove all but the last name in the sorted list (though it won't
request the right name from a 1.6.9 server -- we might just want to bump
up the minimum protocol version to 17 to avoid interacting with anything
older than 1.7.0).

This also means that if we change which file gets removed (switching
back to leaving the last name) we'd need to bump the protocol number
and add some compatibility code for older versions.  Ick.

..wayne..