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Comment by janvdberg | Hacker News Reader

One tip for your .bashrc I only recently found out and can't do without anymore is one I picked up here (log all shell commands directly to a file): https://www.jefftk.com/p/you-should-be-logging-shell-history

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You can get similar behavior with bash's built-in history by setting a few options:

    # -------- History --------
    #increase bash history
    HISTFILESIZE=10000000
    HISTTIMEFORMAT="%FT%R "
    HISTSIZE=10000000
    # append to .bash_history and reread after each command
    export PROMPT_COMMAND="history -a;$PROMPT_COMMAND"
    # append to .bash_history instead of overwriting
    shopt -s histappend
    # dont allow repeated lines
    export HISTCONTROL=ignoredups:erasedups

wondering if scanning throu >10M history entries, looking for duplicates, will introduce a noticeable ex degradation on lesser systems (rpi etc).

The file might fit without much problems in the filesystem cache, so i guess it would only be a problem in the first time.

I had a friend in university that used a refurbished hp workstation with a shitload of ram as a desktop computer, and he would find | xargs -L1 cat {} > /dev/null everything in his home directory on login to warm up the filesystem cache. The kernel would then drop stuff not actually needed/accessed nicely over time.

Don't know about erasedups, but the other option just applies to consecutive repeats, so really only had to scan from the end until the first non-dup

Except if you ever accidentally open a shell without those settings set (ex: "bash --norc" to get a clean profile) it will trim your decades-long history.

Your HISTFILESIZE is also probably not enough: my .full_history goes back to 2012 and is 2.5x your limit.

Curiously, I'm observing in bash 5.0-6ubuntu1.2 that tidily appending the above to the default ~/.bashrc does not work: The variables appear overwritten as intended when inspected, but upon shell exit, the first-set values (from first few lines of .bashrc e.g. HISTFILESIZE=2000) control the update to .bash_history.

Anyone else see this in the bash distro? Seems to be a regression.

The fix of course is to simply delete or hack a '#' into the start of the unwanted lines from the default .bashrc.

I like saving all my history, but I also find that it easily becomes a mess doing it in one file. So I split it up session, and then I merge it all into one file.

  # Eternal bash history.
  # ---------------------
  HISTCONTROL=
  HISTFILESIZE=
  HISTIGNORE=
  HISTSIZE=
  HISTTIMEFORMAT="%Y-%m-%dT%T%t"

  # read global history
  HISTFILE=~/.bash_eternal_history
  history -r
  # IIF there's no session history directory, create one
  if [ ! -d ~/.bash_history ]; then
    [ -f ~/.bash_history ] && mv ~/.bash_history ~/.bash_history.0
    mkdir ~/.bash_history
  fi
  # change history file to one for the session
  HISTFILE=~/.bash_history/$$
  # If it already exists, take a backup
  if [ -f "$HISTFILE" ]; then
    mv "$HISTFILE" "$HISTFILE"."$(stat "$HISTFILE" --format='%W')"
  fi
  # save the current session id + process id
  { export SESSION_ID="$(</proc/$$/sessionid)"; } 2> /dev/null
  printf "#$(date '+%s')"'\n# starting session:'$SESSION_ID' process:'$$' in:'"$PWD"'\n' > "$HISTFILE" &&
    history -r

  # Use trap to save history, not just on logout but also EXIT
  trap_exit() {
    # Append session history to global history
    ## Append to local history session to file
    cp -f "$HISTFILE" /tmp/history.$$.0
    history -a
    cp -f "$HISTFILE" /tmp/history.$$.1
    ## Append local history file to global history
    printf "#$(date '+%s')"'\n# ending session:'$SESSION_ID' process:'$$' in:'"$PWD"'\n' |
        cat "$HISTFILE" - >> ~/.bash_eternal_history
  }
  trap trap_exit EXIT

This looks super interesting. I'll give this a go for a while to see how much I like it.

I like to use atuin for this. Basically indispensable to me now.

https://github.com/ellie/atuin

Great Atuin, that's amazing. Thank you, this is indeed a game changer for having a permanent history. I use ctrl+r for everything including commands I vaguely remember but know at least some letters

I have never felt the need to explicitly lookup history since I switched to fish shell. It has very good command completion (from history).

It’s indispensable in some workflows. Scoring history can help with otherwise difficult debugging, or looking up a variant to a complicated invocation that’s not the one suggested by auto complete.

'histgrep' is an interesting one. Bash has a built in backwards search via ^r, which is greatly enhanced by plugging fzf into it.

Idk, the times I grep history I just history | grep

Using fzf for backwards search sounds interesting, can you elaborate?

My favorite is binding key-up and down to complete using search. That's a game changer

The best description I found with a not so short Google was buried in https://www.redhat.com/sysadmin/fzf-linux-fuzzy-finder but the workflow is I hit ctrl-R (in bash, but there's bindings for other shells), I type out part of the command I know is in my history, and fzf will grep history for commands that match via its fuzzy search algorithm. So if I remember running something that involved a file called something in a log dir, I type /log/, and it interactively lets me search. I remembered I was using awk with the log file, so I can add "awk" to the existing search), and then I use the up arrow to select it and hit enter. at which point it's in my command buffer waiting for me to either hit enter again or edit the command and then hit enter.

Might sound complex written out like that, but I promise it's worth the investment to set it up and read the manual.

this is what mcfly does but it does it all automagically and stores everything in sqlite database. Also easy to sync that db between two computers connected by tailscale/ssh.

If you like searching your Bash history with fzf, you're gonna love McFly: https://github.com/cantino/mcfly

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