Can you prevent a command from going into the bash shell command history? [closed]

Question

Is there a way to prevent a command from being added to the bash shell's command history?

I would like to be able to prevent certain "dangerous" commands from being added to the history, such as "rm -rf ~/some/dir", so that it is not accessible to me by pressing the up-arrow to reach previous commands. In this way, it would not be possible to accidentally repeat one of these commands.

The reason I ask is that I use the up arrow a lot to access previous commands in the shell history, and have often caught myself about to hit enter on what I thought was the correct command, only to realise that I was about to do something stupid/annoying/dangerous. I don't like the idea of rms etc floating around in my shell history, waiting for me to step on them!

(Note: I am aware that one can set up patterns in HISTIGNORE, but what would be nice is something one can apply on a per-command basis, which would become good a habit. Unless there is a clever way to achieve this using HISTIGNORE that I have missed?)

Answer 1

On newer Bash Versions you could simply add a space at the beginning of your command. :) If it doesn't work by default, add [ \t]* to HISTIGNORE. (As mentioned in the comments. thx)

Answer 2

Add ignorespace to your HISTCONTROL environment variable. Then any command line that begins with a space won't be entered into your history.