1

I often find myself searching in my history by doing something like

history | grep searchterm

This returns a list of all the times that I used searchterm in a command. However, I would often like to know the n previous commands and the m next commands that I entered before and after that command which contained searchterm. Often the context in which I ran a command is very useful.

What I would like to be able to do is

> history-search-context searchterm n m

and get separated lists of commands that were entered n commands before and m commands after any history entry that contains searchterm.

Example:

> history-search-context mycommand 2 1

687 cd some/directory
688 ls -a
689 mycommand -flag arg1
690 touch file
-------------
943 apt-get install something
944 pwd
945 mycommand -otherflag arg1 arg2 arg3
946 rm file

This would tell me that I used mycommand twice in recorded history with some interesting flags and arguments, and within a window of [-2,+1] commands I had one time run it in some/directory and had to create a file, and the other time, I installed something, checked which directory I was in, and then deleted file.

Is there an existing way to do this? If not, how to accomplish this?

  • If my answer solved your problem, please accept it by clicking the checkmark next to it. Thank you! – Jeff Schaller Feb 17 at 13:45
0

I would approach it with a helper function and grep, since (GNU) grep has a natural set of options for "lines before & after the match". The bare-bones version is:

histgrep() {
  history | grep -B $2 -A $3 "$1"
}

... and you'd use it just like your history-search-context command above:

$ histgrep jeff 1 1

  517  vi go.sh
  518  x=jeff
  519  y=/tmp
--
  832  sudo visudo
  833  sudo adduser jeff2
  834  man sudoers
--
  841  sudo ls -al /var/lib/sudo/lectured
  842  sudo rm /var/lib/sudo/lectured/jeff /var/lib/sudo/lectured/schaller
  843  sudo ls
--
  940  ls *[[:digit:]][[:digit:]][[:digit:]][[:digit:]][[:digit:]]*
  941  touch jeff߄߅߆߇߈߉.txt
  942  ls
--
 1235  histgrep a b c
 1236  histgrep jeff a 1
 1237  histgrep jeff 1 a
 1238  histgrep jeff 1 1

After adding some basic error-checking the function would be:

histgrep() {
  if [ "$#" -ne 3 ]
  then
    echo "Usage: histgrep searchterm n-before m-after"
    return
  fi
  case "$2$3" in
  (*[^0-9]*)
        echo "Usage: histgrep searchterm n-before m-after"
        return
        ;;
  esac
  history | grep -B $2 -A $3 "$1"
}

You could easily enough name it history-search-context instead of histgrep if you wanted:

history-search-context() {
# ...
}
  • This is exactly what I was looking for. Perfect. Thanks so much for the solution. – user10108 Feb 10 at 21:21

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