Bash history settings to tweak for infinite history, instant appending of commands, and shared history across multiple terminals.

bashrc.sh

# By Pete Warden, @petewarden
# To use this, open ~/.bashrc in your editor of choice,
# and place these settings at the end.
# Based on https://unix.stackexchange.com/a/48113 and
# https://blog.sanctum.geek.nz/better-bash-history/

# Ignore both duplicate commands, and those that start with a space.
HISTCONTROL=ignoreboth

# Append to the history file, don't overwrite it.
shopt -s histappend

# Make the maximum size of the history file enormous.
HISTSIZE=1000000
HISTFILESIZE=20000000

# This makes the entries easy to sort by time.
HISTTIMEFORMAT='%F %T '

# Store each command in the history immediately, not on session close.
PROMPT_COMMAND="history -a; history -c; history -r; $PROMPT_COMMAND"