tar-copy overwrites silently

[Robert Marshall]

If you open a tar archive in tar-mode, it looks rather like dired mode
Where it differs (amongst other things) is that if you tar-copy (bound
to C as in dired-mode) it doesn't check before extraction that the
file already exists and it doesn't then warn you!

I realise that tar doesn't have this behaviour but if you're using tar
mode and tar-copy because you realise there are possible overwriting
problems and you make a mistake.... :-(

Suggest that there should be some handling of this along the lines of 
dired-backup-overwrite

Robert
-- 
Robert Marshall