Is it currently/technically possible to display the current date & time (ie: digital clock numbers) to the currently active window? Like appending some text from a script?


Showing date & time in the active window's title

Running the script below (an edited version of this one) in the background, the front most window will show the current date & time:

enter image description here

If the window loses focus, the time will not be updated; only on the front most window, the time will be updated.
The script also shows the date & time per tab on any application using tabs, like firefox or gnome-terminal

The script

#!/usr/bin/env python3
import subprocess
import time

cmd = "xdotool", "getwindowfocus"
get_name = "xdotool", "getactivewindow", "getwindowname"

currtime_1 = time.strftime("%d-%m-%Y  %H:%M"); wid_1 = subprocess.check_output(cmd).decode("utf-8").strip()
wname_1 = subprocess.check_output(get_name).decode("utf-8"); wname_1 = wname_1[:wname_1.rfind(" |  ")]

while True:
    currtime_2 = time.strftime("%d-%m-%Y  %H:%M")
        wid_2 = subprocess.check_output(cmd).decode("utf-8").strip()
        wname_2 = subprocess.check_output(get_name).decode("utf-8"); wname_2 = wname_2[:wname_2.rfind(" |  ")]
        if any([wid_2 != wid_1, currtime_2 != currtime_1, wname_2 != wname_1]):
            cmd2 = ["xdotool", "set_window", "--name", wname_2+" |  "+str(currtime_2), wid_2]
        currtime_1 = currtime_2; wid_1 = wid_2
    except subprocess.CalledProcessError:

How to use

  1. The script uses xdotool

    sudo apt-get install xdotool
  2. Copy the script below into an empty file, save it as show_datetime.py

  3. Test-run it by the command:

    python3 /path/to/show_datetime.py

    Open a new window or give an existing one focus. The date & time should appear in the window's title within 1-2 seconds. Wait a minute to see if the time is updated.

  4. If all works fine, add it to your startup applications: Dash > Startup Applications > Add, add the command:

    python3 /path/to/show_datetime.py
  5. If you are having difficulties running it from start up, use the command (in startup applications):

    /bin/bash -c "sleep 20&&python3 /path/to/show_datetime.py"


The script keeps an eye on three things:

  • The frontmost window's id
  • The frontmost window's name
  • The current time (minute)

If there is a change in either one, the date/time is appended or updated to the currently frontmost window.

Why use the name -and- the id of the window?

  • The window- id is used to set the window's title, to prevent setting the wrong window (terminal windows e.g. can be named similarly).
  • The window- name is to include tabbed windows, e.g. Firefox. The window name will change when another tab is chosen or opened, while the window- id won't change.
  • The conditional if any([]) is to edit the window's title only if there is a reason to.
  • Works flawlessly. – mancvso Jun 11 '15 at 18:17

It's a simple shell script:


  • xdotool

    sudo apt-get install xdotool
  • wmctrl

    sudo apt-get install wmctrl

Main part

wmctrl -r :ACTIVE: -N "$(awk -F' \\|\\|' '{print $1}' <<< $(xdotool getwindowfocus getwindowname)) || $(date "+%Y-%m-%d %H:%M:%S")"

The || is the separator between the window title an the date/time part. If you need another one, change it, eg:


wmctrl -r :ACTIVE: -N "$(awk -F' #' '{print $1}' <<< $(xdotool getwindowfocus getwindowname)) # $(date "+%Y-%m-%d %H:%M:%S")"

The script

while true
    wmctrl -r :ACTIVE: -N "$(awk -F' \\|\\|' '{print $1}' <<< $(xdotool getwindowfocus getwindowname)) || $(date "+%Y-%m-%d %H:%M:%S")"
    sleep 5
  • sudo apt install wmctrl was needed. Works perfectly. – mancvso Jun 11 '15 at 18:19

Here's a script that utilizes bash, xprop, and wmctrl (does not come with ubuntu). This script can be added as an autostart entry or placed into .desktop file. Basic idea is to get current active window's id, store its current title, and use output of date command and title to form a new title. The if statement prevents infinite loop of appending date. You can get wmctrl with sudo apt-get install wmctrl . Otherwise this script is very simplistic but does the job well enough.

# Date : June 9 2015
# Author: Serg Kolo
# Description: script to append time to window titles
while sleep 1; do
        ACTIVEID=$(xprop -root | awk '/^_NET_ACTIVE_WINDOW/ {gsub("0x","0x0");print $5}')
        MATCHED_TITLE="$( wmctrl -l | awk -v searchterm=$ACTIVEID   '$0~searchterm {for(i=4;i<=NF;i++) printf $i" "}')"
        date --date="$(echo $MATCHED_TITLE | awk '{print $1" "$2}')"  > /dev/null  2>&1

        if [ "$?" -eq 0 ]; then
                MATCHED_TITLE="$(echo $MATCHED_TITLE | awk '{for(i=3;i<=NF;i++) printf $i" "}')"
        sleep 1
        wmctrl -i -r $ACTIVEID -T "$(date +"%D %H:%M" 2>/dev/null) $MATCHED_TITLE "

  • Gets the job done. The window title is lost though. – mancvso Jun 11 '15 at 18:22
  • @dael99 interesting. Is it lost only in terminal ? or on other programs as well ? Please let me know, so I can improve my answer – Sergiy Kolodyazhnyy Jun 11 '15 at 18:25
  • Lost in other windows as well (like Firefox) – mancvso Jun 11 '15 at 18:41
  • @dael99 interesting. I've tested this multiple times, still works on all the windows. Can you please add set -x at the beginning of the script, after #!/bin/bash , and let me know if any of the variables are not being set ? – Sergiy Kolodyazhnyy Jun 11 '15 at 18:56

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