Repeat a Command with sudo

Repeat a Command with sudo

You most probably found yourself in the situation of running a command, and after hitting enter to realise that it should’ve been ran in a sudo context.

Usually, you’d hit up and go to the beginning of the command and type sudo, or {insert handy approach here}

There is a geekier way to do that. You can type:

In result, bash will expand the two exclamation points to the previous command and it will be run through sudo.
Sudo Repeat Command

The shell scans the results of parameter expansion, command substitution, and arithmetic expansion that did not occur within double quotes for word splitting.

The shell treats each character of $IFS as a delimiter, and splits the results of the other expansions into words on these characters. If IFS is unset, or its value is exactly “‘‘”, the default, then any sequence of IFS characters serves to delimit words. If IFS has a value other than the default, then sequences of the whitespace characters “space” and “Tab” are ignored at the beginning and end of the word, as long as the whitespace character is in the value of IFS (an IFS whitespace character). Any character in IFS that is not IFS whitespace, along with any adjacent IF whitespace characters, delimits a field. A sequence of IFS whitespace characters is also treated as a delimiter. If the value of IFS is null, no word splitting occurs.

Explicit null arguments (“””” or “””) are retained. Unquoted implicit null arguments, resulting from the expansion of parameters that have no values, are removed. If a parameter with no value is expanded within double quotes, a null argument results and is retained.