Sanitising command before storing it in bash history

Question

Upon accidentally running the wrong command because of an incomplete Ctrl-R search and rm -rfing a file I needed, it got me thinking.

Is there a way to sanitise rm -rf foo to be saved in bash history as rm -r foo?
This will ensure if the command is accidentally run in the future, it will ask before doing so.
My rm is aliased to rm -iv, so I think this stops rm -r from removing without asking (I admit I have not run rm -r without the -i flag)

The reason I think this is possible is based on the bash bang builtins.

mkdir foo
cd !$

Will show in bash history:

mkdir foo
cd foo

Edit: while I appreciate the "don't save in history at all" solutions, I am aware of it and specifically wanted a different solution, as @tripleee explained.

See also: http://unix.stackexchange.com/questions/32460/excluding-some-of-the-commands-from-being-getting-stored-in-bash-history — codeforester, Mar 03 '17 at 03:36
Possible duplicate of [How to prevent commands to show up in bash history?](http://stackoverflow.com/questions/6475524/how-to-prevent-commands-to-show-up-in-bash-history) — codeforester, Mar 03 '17 at 03:39
With your alias, `rm -rf` expands to `rm -iv -rf`, so the `-f` overrides the preceding `-i`. — chepner, Mar 03 '17 at 03:48
While the nominated dupicate is probably the only sane answer (i.e. basically "don't do that") it doesn't directly answer the OP's question. I interpret this to mean "is there a facility to somehow filter what ends up in the history" (the answer to which is no, though Chepner's answer intriguingly offers a way to do roughly that) rather than "how do I completely remove some commands from the history" (which is a different thing, and easy to do). — tripleee, Mar 03 '17 at 05:06

chepner · Accepted Answer · 2017-03-03T04:26:02.423

I'm not sure how foolproof this is; it might miss some way of supplying the -f option. That said, you can override rm with the following:

rm () {
  local HISTIGNORE="$HISTIGNORE:command rm *"
  local arg process
  local -a sanitized
  command rm "$@"
  process=true
  for arg in "$@"; do
    if [[ $process && $arg = -*f* ]]; then
      sanitized+=("${arg//f/}")
    elif [[ $arg == -- ]]; then
      process=
    else
      sanitized+=("$arg")
    fi
  done
  history -s rm "${sanitized[@]}"
}

This works as follows:

Temporarily add the pattern command rm * to the HISTIGNORE list, so that the command about to be executed isn't added to history.
Execute the command as requested.
Walk through the arguments, looking for any that contain the -f option. (Either standalone or in a cluster of short options.) Any such word should have the f removed. Sanitized words are added to a new array.
The history -s command adds the reconstructed command (with sanitized arguments) to the history list.

This is a really interesting way to solve this. Because of my alias, this shows in history as `rm -iv -r foo` but it's still excellent. Re-running the command asks me before deleting anything. Thank you. — Trav Easton, Mar 03 '17 at 08:47

Sanitising command before storing it in bash history

1 Answers1