Re: [Mingw-users] mv -f can't overwrite

[Keith M. <kei...@us...>]

On Monday 29 June 2009 06:03:36 leledumbo wrote:
> > You've said to move a directory A/C and a directory B/C to the
> > current working directory.  I don't think that is want you meant
> > to do.
>
> Actually, it is.

Really?  You do astound me!  However, if that *really* is what you 
want, this will get the job done:

  $ rm -rf ./C && mv A/C . && rm -rf ./C && mv B/C .

but then why go to this length?  You might just as well:

  $ rm -rf A/C ./C && mv B/C .

which is a simpler way to achieve identically the same objective.

Now, tell me again: is that *really* what you wanted to do?  I think 
not, and that Earnie was quite right; you really wanted to *merge* 
the *content* of two existing directories into a common tree, while 
removing the originals in the process, which you might achieve with:

  $ rm -rf ./C && mv A/C ./C && mv B/C/* ./C

However, this will still fail, if A/C and B/C have any similarly 
named subdirectory, (at any level in the hierarchy), which is not 
empty in the original A/C tree.

> > With more modern systems, where cp supports the `-p' and `-r'
> > options, (as MSYS' cp does), you could also use (untested):
> >
> >   $ mv -f A/C . && cp -prf B/C/* C && rm -rf B/C
>
> Aha! Good idea, I'll try it.

Do note that the `-f' option to `mv' is pretty much redundant here; 
in the command:

  $ mv -f src dest

`-f' takes effect only if `dest' represents an existing *file* or 
*empty* directory, for which you lack write permission, but you do 
have permission to `chmod' it, to make it writeable, so that it may 
be unlinked; a *non-empty* directory can never be unlinked, even if 
you do have write permission, unless you first recursively remove 
all of its content, (which `mv' will never do for you).

-- 

Regards,
Keith.