Re: I'am root user, but 'emacs /etc/sudoers' still report Buffer is read-only: #<buffer sudoers> in modeline

[Bob Proulx]

Show Dont wrote:
> I want to edit /etc/sudoers for add 'git ALL=(ALL:ALL) ALL' in it. I
> am ready the root user, but emacs still can not edit the
> /etc/sudoers.

Use C-q C-x to toggle read-only status.  It starts off read-only
because the file permissions are read-only.  If you are the root
superuser then you can toggle the buffer read-only status and then
edit the file anyway and override the file permissions on save and
write the file anyway.

Here is the documentation.

  https://www.gnu.org/software/emacs/manual/html_node/emacs/Misc-Buffer.html

Specifically for the suders file it is a good idea to use the
'visudo' command to edit that file.  It will make a copy of the file
for editing and then will validate the syntax before saving.  It
prevents typos and accidents breaking the sudo configuration, which
might prevent a sudo only user from having sudo to fix the problem.
'visudo' respects the EDITOR variable and will invoke emacs as the
editor if EDITOR is set to emacs.

I highly recommend using the visudo command for editing the
/etc/sudoers file.  It will make a writable copy and therefore you
won't need to toggle the read-only status.

Bob