Directory RSync help with a twist..

Question

I wish to sync two directories of multiple folders and files (mp3s). Using rsync I have managed to create one master set of directories from the original two...but with unwanted duplicates
If a number of files are identical (jazz.mp3, rock.mp3 etc.) but are located in different directories in both locations, how can avoid/exclude copying them across and therefore creating duplicates of the files.
e.g. /new/jazz.mp3
and /old/jazzfiles/jazz.mp3
using rsync -r /old /new
would result in two directories in /new
/new/jazz.mp3
and /new/old/jazzfiles/jazz.mp3
If someone understands what I am getting at...any pointers much appreciated.
Joel.

Answer 1

I'm not certain, but it sounds like you should to look at rsync's --compare-dest switch:
--compare-dest=DIR
This option instructs rsync to use DIR on the destination
machine as an additional hierarchy to compare destination files
against doing transfers (if the files are missing in the desti-
nation directory). If a file is found in DIR that is identical
to the sender's file, the file will NOT be transferred to the
destination directory. This is useful for creating a sparse
backup of just files that have changed from an earlier backup.
so something like:
rsync -r -compare-dest=/new/jazzfiles /old /new
The command specifically references destination directories, though, but it sounds like you want to compare multiple source directories. I have no idea off hand whether the above still applies.