Use “history” command to fire last run command?

Question

How do I use the "history" command to fire the last run command?

Answer 1

You wouldn't. You'd use !!.

Answer 2

As Ignacio said, use !!, but if you insist:

$(history | sed '$d' | sed -n '$p' | cut -d ' ' -f 3-)

Explanation:

• $() executes the output of the command inside
• sed '$d' deletes the last command, i.e. 2001 $(history | sed '$d' | sed -n '$p' | cut -d ' ' -f 3-)
• sed -n '$p' prints only the last line, i.e. 2000 yourpreviouscommand
• cut -d ' ' -f 3- removes the first three fields, separated by spaces, i.e. <space>2000<space>

I think it can be made more concise and robust, but it works for now.

Edit: If you want to use history instead of !! because the shell you're using doesn't have !!, you're out of luck; history is a shell built-in, not a program. And simple shells are not likely to have it if they don't have !!. For example, dash doesn't:

imgx64@home:~$ dash
$ history
dash: history: not found
$ 

Answer 3

In Bash, the fc command may do what you're looking for.

From man bash:

...
In the second form, command is re-executed after each instance of pat is replaced by rep. A useful alias to use with this is r="fc -s", so that typing r cc runs the last command beginning with cc and typing r re-executes the last command.
...