Emacs normally does not save backup files for source files that are
maintained with version control. If you want to make backup files even
for files that use version control, set the variable
vc-make-backup-files to a non-nil value.
Editing a version-controlled file through a symbolic link may cause
unexpected results, if you are unaware that the underlying file is
version-controlled. The variable vc-follow-symlinks controls
what Emacs does if you try to visit a symbolic link pointing to a
version-controlled file. If the value is ask (the default),
Emacs asks for confirmation. If it is nil, Emacs just displays
a warning message. If it is t, Emacs automatically follows the
link and visits the real file instead.
If vc-suppress-confirm is non-nil, then C-x v v
and C-x v i can save the current buffer without asking, and
C-x v u also operates without asking for confirmation.
VC mode does much of its work by running the shell commands for the
appropriate version control system. If vc-command-messages is
non-nil, VC displays messages to indicate which shell commands
it runs, and additional messages when the commands finish.