--no- usage

[Paul Slootman]

The manpage states:

    You may turn off one or more implied options by prefixing the option
    name with "no-". Not all options may be prefixed with a "no-": only
    options that are implied by other options (e.g. --no-D, --no-perms)
    or have different defaults in various circumstances (e.g.
    --no-whole-file, --no-blocking-io, --no-dirs). You may specify
    either the short or the long option name after the "no-" prefix
    (e.g. --no-R is the same as --no-relative).

The distinction which options are implied or not isn't that clear...
In the case of the -a string of options it's not a problem, but I can't
see how --relative could be an implied option; however, it's given as an
example of the usage of --no-.

I looked into this because I wanted to "comment out" the usage of
--checksum quickly in a script, and thought that sticking -no- before
the word "checksum" would work; however:
rsync: --no-checksum: unknown option

So apparently not all options can cope with the --no- thing. Perhaps
this should be made clear in the manpage? (Or is it an error?)


Paul Slootman