commandliners

Bash provides a powerful history system that helps you in repeating commands and arguments.

For example, the !! command, repeats the last executed command.

If you want to execute a command typed before the last one, you can select it with the following:

!-number

Something like this:

$ ls
$ ps
$ !-2

The last command executes ls again.

In addition, you can specify previous arguments too. This is done with the !:n command (n being a number). Let’s see an example:

$ less file.txt
$ cp !:1 file_copy.txt

The last command takes the first argument of the previous executed command and makes a copy with a different name.

If this is not enough for you, you can select a certain parameter of an arbitrary previously executed command. In order to do this, you have to join the two command we have seen so far.

$ ls file1.txt file2.txt
$ ps
$ echo !-2:1

This prints file

Have fun!