Emacs' TRAMP feature (Transparent Remote file Access, Multiple Protocol) is an extremely powerful tool for editing files that exist on remote systems, or require access using a different user account from your main Emacs session, or both.
Some of the things that TRAMP can do include:
* Editing files on a remote development server over SSH (e.g.
<code>/ssh:firstname.lastname@example.org:/path/to/my/file </code>)* Editing files on your local machine as root via sudo (e.g. <code>/sudo::/etc/some/config/file </code>)* Editing files on a remote server as root via sudo over an SSH connection from another remote machine that exists within a DMZ (requires a little bit of configuration)
TRAMP is included with Emacs and described in the manual.