--csum-length ?!

[Paul Slootman]

>From the manpage:

--csum-length=LENGTH
        By  default  the primary checksum used in rsync is a very strong
        16 byte MD4 checksum. In most cases you will find that  a  trun-
        cated version of this checksum is quite efficient, and this will
        decrease the size of the checksum data sent over the link,  mak-
        ing things faster.

        You  can  choose  the  number of bytes in the truncated checksum
        using the --csum-length option. Any value less than or equal  to
        16 is valid.

        Note that if you use this option then you run the risk of ending
        up with an incorrect target file. The risk with a value of 16 is
        microscopic  and can be safely ignored (the universe will proba-
        bly end before it fails) but with smaller  values  the  risk  is
        higher.

        Current versions of rsync actually use an adaptive algorithm for
        the checksum length by default, using a 16 byte file checksum to
        determine  if  a 2nd pass is required with a longer block check-
        sum. Only use this option if you have read the source  code  and
        know what you are doing.

Of course, if you've read the source code, you'd know that there's no
such option :-) So, I request that this be removed from the manpage.


Paul Slootman