How to edit what is typed in command line?

Question

Typing a command like:

cat somefile

1. Press enter and run the command.

2. Then searching for it using ESC + k, allows me to bring it back.

I want to go back and edit the command while still typing in the prompt. From what I understand, ESC + o would allow me to type over or go back what I wrote in the command.

However, those hotkeys do not seem to work, after the initial press. Though I am however able to edit after a few key presses of the arrow keys. Is there another way to edit command in the prompt that is retrieved using ESC + k?

Answer 1

When you get the commandline-prompt, you are ready for inserting code:
You are in the vi edit mode.
You can look up a vi manual, here some commands for the commandline:

• ESC Leave the insert mode and enter the command mode.
• ESC /somecommand ENTER n n Look for somecommand. n n are looking for the next twice
• ESC wwb3w Go forward 2 words, back 1 word and forward 3 words
• ESC dwxx Delete word and two timews 1 character
• ESC lllcw 3 positions to the left, change word
• ESC wrs Go forward 1 word and replace character by an s

Answer 2

Yes, There is. You can use "!!" for previous command. For Example:

$ cat file.txt
$ !! file2.txt # this will output both file.txt and file2.txt

Also you can pipe them to other commands.

$ !! | some_command  # it will pipe just previous command's output to some_commands

AND... If you want to execute 5th previous command

$ !-5

if you don't know the order of that command then,

$ history
233 cat file.txt
234 ls
235 date
$!234 # this will execute ls command