receiving side to hold an additional  copy  of  all  the  updated
              files.   Note  also  that  you should not use an absolute path to
              --partial‐dir unless:

              1.     there is no chance of any of the  files  in  the  transfer
                     having  the same name (since all the updated files will be
                     put into a single directory if the path is absolute), and

              2.     there are no mount points in the hierarchy (since the  de‐
                     layed  updates  will  fail  if  they can’t be renamed into
                     place).

              See also the "atomic‐rsync" python script in the "support" subdir
              for an update algorithm that is even more atomic (it uses --link‐
              dest and a parallel hierarchy of files).

       --prune‐empty‐dirs, -m
              This option tells the receiving rsync to get rid of empty  direc‐
              tories from the file‐list, including nested directories that have
              no  non‐directory children.  This is useful for avoiding the cre‐
              ation of a bunch of useless directories when the sending rsync is
              recursively scanning  a  hierarchy  of  files  using  include/ex‐
              clude/filter rules.

              This  option  can  still leave empty directories on the receiving
              side if you make use of TRANSFER_RULES.

              Because the file‐list is actually being pruned, this option  also
              affects  what  directories  get  deleted when a delete is active.
              However, keep in mind that excluded  files  and  directories  can
              prevent  existing items from being deleted due to an exclude both
              hiding source files and protecting destination  files.   See  the
              perishable filter‐rule option for how to avoid this.

              You can prevent the pruning of certain empty directories from the
              file‐list by using a global "protect" filter.  For instance, this
              option would ensure that the directory "emptydir" was kept in the
              file‐list:

                  ‐‐filter ’protect emptydir/’

              Here’s an example that copies all .pdf files in a hierarchy, only
              creating  the  necessary destination directories to hold the .pdf
              files, and ensures that any superfluous files and directories  in
              the destination are removed (note the hide filter of non‐directo‐
              ries being used instead of an exclude):

                  rsync ‐avm ‐‐del ‐‐include=’*.pdf’ ‐f ’hide,! */’ src/ dest

              If  you  didn’t want to remove superfluous destination files, the
              more time‐honored options of  --include=’*/’ --exclude=’*’  would
              work fine in place of the hide‐filter (if that is more natural to
              you).

       --progress
              This option tells rsync to print information showing the progress
              of  the  transfer.   This  gives a bored user something to watch.
              With  a  modern  rsync   this   is   the   same   as   specifying
              --info=flist2,name,progress,  but  any user‐supplied settings for
              those      info      flags      takes      precedence       (e.g.
              --info=flist0 --progress).

              While rsync is transferring a regular file, it updates a progress
              line that looks like this:

                  782448  63%  110.64kB/s    0:00:04

              In  this  example, the receiver has reconstructed 782448 bytes or
              63% of the sender’s file, which is being reconstructed at a  rate
              of 110.64 kilobytes per second, and the transfer will finish in 4
              seconds if the current rate is maintained until the end.

              These  statistics can be misleading if rsync’s delta‐transfer al‐
              gorithm is in use.  For example,