bug#10489: 24.0.92; dired-do-copy may create infinite directory hierarchy

[Michael Albinus]

Thierry Volpiatto <thierry.volpiatto@gmail.com> writes:

> Now we have an error until you write handlers:
>
> tramp-file-name-for-operation: unknown file I/O primitive:
> file-subdir-of-p
>
> This happen when copying with sudo method.

Should be fixed now.

Btw, it might be useful if you could add documentation about
`files-equal-p' and `file-subdir-of-p' in doc/lispref/files.texi.

Best regards, Michael.