bash: print command execution time and exit code.

.bashrc

function __timer_now {
   printf %s "${EPOCHREALTIME//\./}"
}

function __timer_start {
    timer_start=${timer_start:-$(__timer_now)}
}

function __timer_stop {
    local delta_us=$(($(__timer_now) - timer_start))
    local us=$((delta_us % 1000))
    local ms=$(((delta_us / 1000) % 1000))
    local s=$(((delta_us / 1000000) % 60))
    local m=$(((delta_us / 60000000) % 60))
    local h=$((delta_us / 3600000000))
    # Goal: always show around 3 digits of accuracy
    if ((h > 0)); then timer_show=${h}h${m}m
        elif ((m > 0)); then timer_show=${m}m${s}s
        elif ((s >= 10)); then timer_show=${s}.$((ms / 100))s
        elif ((s > 0)); then timer_show=${s}.$(printf %03d $ms)s
        elif ((ms >= 100)); then timer_show=${ms}ms
        elif ((ms > 0)); then timer_show=${ms}.$((us / 100))ms
        else timer_show=${us}us
    fi
    unset timer_start
}

function __print_status {
    exit_code="$?"

    __timer_stop

    local PS_RIGHT="[$timer_show] "
    local PS_RIGHT_NC="$PS_RIGHT"

    if [ "${exit_code}" -ne 0 ]; then
        PS_RIGHT="\e[01;31m${exit_code}\e[00m $PS_RIGHT"
        PS_RIGHT_NC="${exit_code} $PS_RIGHT_NC"
    fi

    tput sc
    echo -ne "\r"
    tput cuf $(($(tput cols) - ${#PS_RIGHT_NC}))
    echo -ne "${PS_RIGHT}"
    tput rc
}

trap '__timer_start' DEBUG

PROMPT_COMMAND=__print_status

example.png