What exactly is sudo bang bang? [closed]

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Closed 7 years ago.

What is the purpose of sudo bang bang (sudo !!) and when might one need to use it?

回答1:

The bang bang (!!) command is a shortcut to repeat the previous command you entered in your terminal. This command is very useful when you forget that you need admin rights to make a certain action, and lets you repeat it with super-user rights just by typing

sudo !!

instead of typing arrow-up, scrolling to the beginning of the line, adding sudo and hitting enter (imagine scrolling through those loooong apt-get commands). So many seconds gained! Yay!

There are many other bang-commands such as !x, !?x, !!:p and !!*. This blog post lists them and explains what they are for.