[overgun77]

Not really a unix command, but a vi command that has been really useful, specially if you do lots of editing protected files and want to keep your custom vim configuration:

!sudo tee %

[sousousou]

Need to send the contents of the file to that command. Otherwise it effectively empties the file. (typo?)

:%!sudo tee %

[ralph]

What vi mode is that entered in?

[emillon]

Normal mode (:help :! for more information on this command).

[ralph]

What benefit does

    :!sudo tee %

have over doing it at the command line other than filling in the current filename for you? I suspect the original poster meant something like "gg!Gsudo tee %".

[AjithAntony]

:w !sudo tee %