cp -u should skip copying a file to itself

[Ed Avis]

% touch foo foo
% cp -u foo foo && echo yes
cp: `foo' and `foo' are the same file

I expected that since -u says

       -u, --update
              copy only when the SOURCE file is newer than the
              destination file or when the destination file is missing

it would not attempt to copy the file in this case (since the file is 
not newer than itself) and cp would return a true exit status.

--
Ed Avis <address@hidden>