bash: infinite history and a nice prompt

Recently I deleted my .bashrc and .bash_history by mistake. I lost a good deal of dear commands plus aliases and needed to come up with another .bashrc to get infinite history and a nice prompt.

There are often one-off commands for some very specific tasks that are rarely used but very useful. Such one-offs often are forgotten and not explicitly saved. When they are required though, I am very happy to just make Ctrl-r on my terminal and write a few fragments that I remember and then they come up. It is like my own toolbox. For that, I rely on the fact that my .bash_history is infinite.

The prompt is also very useful in my day-to-day. Often I have very long-running terminal sessions that have commands whose timestamps and exit codes matter to me over the course of my tasks. Timestamps help me get the duration of the command by checking the timestamp of the command vs the next prompt. The exit code helps me understand if the command was successful, normally much later after it ran, and when I no longer remember some task’s details.

In the course of redoing my .bashrc I leaned on this StackOverflow post and a really nice site that allows one to generate custom PS1(prompt). The result is this

# Eternal bash history.
# ---------------------
# Undocumented feature which sets the size to "unlimited".
# http://stackoverflow.com/questions/9457233/unlimited-bash-history
export HISTFILESIZE=
export HISTSIZE=
export HISTTIMEFORMAT="[%F %T] "
# Change the file location because certain bash sessions truncate .bash_history file upon close.
# http://superuser.com/questions/575479/bash-history-truncated-to-500-lines-on-each-login
export HISTFILE=~/.bash_eternal_history
# Force prompt to write history after every command.
# http://superuser.com/questions/20900/bash-history-loss
PROMPT_COMMAND="history -a; $PROMPT_COMMAND"
export PS1="[\t \$?] \h:\w \[$(tput sgr0)\]"

Edit: You may need to manually sanitize your history from time to time if you by mistake input a secret into the command line. Such a secret will be visible in plain text. Model your threats.

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