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Comment by chongli | Hacker News Reader

Wow, cool! How does this handle the case of multiple shells writing to the history at the same time? I have yet to find a safe way to preserve all that.

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Add this to your .bashrc:

  # History stuff.
  shopt -s histappend
  export HISTFILESIZE=50000
  export HISTSIZE=50000
  export HISTCONTROL=ignoreboth
  export PROMPT_COMMAND='history -a'

Individual shells keep their session history in order, while all commands regardless of which shell triggered them get appended to the history file.

  # infinite history
  HOSTNAME="$(hostname)"
  HOSTNAME_SHORT="${HOSTNAME%%.*}"
  mkdir -p "${HOME}/.history/$(date -u +%Y/%m/)" > /dev/null 2>&1
  SESSIONPREFIX=$(date -u +%Y/%m/%d.%H.%M.%S)
  export HISTFILE="${HOME}/.history/${SESSIONPREFIX}_${HOSTNAME_SHORT}_$$"

Only thing you're missing is `HISTFILE`, and an alias like

  alias histgrep='find ~/.history/ -type f -print0 2>/dev/null | xargs -0 grep --color=auto -InH'

https://news.ycombinator.com/item?id=10162189 for context

Same idea with some usage and backup tips: http://jesrui.sdf-eu.org/remember-all-your-bash-history-fore...

Looking at the script, it doesn't write any history itself, it just loads whatever is in the existing .bash_history into its db when `hist import` is invoked (when a new shell is started if you add it to your .profile like the readme recommends.)

So this does not do anything to manage different sessions clobbering each others' histories. The solution posted by zootboy will work together with this script however.

FWIW, my understanding of sqlite is that it allows atomic operations against the same DB, even if there are different clients... so I would guess at worst the clobbering is minimal. I could be wrong, though.

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