Using a keyboard shortcut in Linux to add an e-mail signature giving current location and local time

In my previous post I showed how to find the current time at any town or city Worldwide from the command line in Gentoo Linux. My interest in a command to do this is not to use it on the command line per se, but to use the command in a keyboard shortcut to insert a signature at the end of my e-mails.

I have to travel internationally frequently because of my work, but I leave my laptop’s hardware clock set to UTC and the system clock set to the local time of my home town. This means that, irrespective of where I am in the World, the e-mail client (Thunderbird, in my case) uses the local time of my home town in e-mail headers and calenders. It is not practical to reconfigure Linux for each timezone I happen to be in (see my post Configuring the Linux clock), and, in any case, I want the file system’s timestamps to use one timezone only and all the timestamps in my e-mails and the e-mail client’s calender to use one timezone only, so there is less chance of me getting confused. I could have configured the installation to use UTC for the system clock, but I prefer the system clock to use the timezone of my home town. Of course, even though the system clock is always set to the timezone of my home town, on the Panel clock I select the timezone of the location where I happen to be, so that the Panel clock displays the local time in that timezone.

I wanted to be able to insert a signature at the end of each e-mail, stating my current location and the current time at that location, so that the person receiving the e-mail could tell from where in the World I sent the e-mail and the local time it was sent, as that local time could differ from the time shown in the e-mail header. For example, let us assume that Jane, who lives in the UK and whose system clock is configured for the timezone Europe/London, is making a brief visit to Perth, Australia and sends an e-mail to Dave in the UK at 06:36 on 11 October (Perth time). The e-mail below illustrates the type of signature I wanted to achieve.

Subject: Site visit
From: Jane <jane@acompany.com>
To: Dave <dave@acompany.com>
Date: Sat Oct 10 2015 23:36:40 GMT+0100 (BST)

Hello Dave,

This is to let you know that I have just arrived in Perth and will be
visiting site at 09:00 local time to speak to the client. Tomorrow p.m.
I have a meeting scheduled with our local project manager, so I would
appreciate it if you would e-mail the latest documentation to me. I will
not have spare time until I’m in my room at the hotel tonight but will
read the documents tomorrow a.m. in readiness for the meeting with
the local project manager. Thanks in advance.

Regards,
Jane
Current location: Perth (Australia)
Local time now: Sat Oct 11 06:36:31 2015 AWST

As you can see above, because the OS on Jane’s and Dave’s laptops is configured for the timezone Europe/London, the e-mail header shows the current time in the UK when the e-mail was sent, which was October 10, 23:36 British Summer Time (22:36 UTC), and the signature shows the corresponding local time in Perth, Australia, which was October 11, 06:36 Australian Western Standard Time. It becomes even more confusing if the computer of the person receiving the e-mail is configured for a third timezone. For example, let’s say Dave is based in Seattle, USA rather than the UK. His e-mail client would then display the time in that timezone when the e-mail was sent. This is usually my case, i.e. my Linux installation is configured for Timezone1 but I happen to be in Timezone2 when I send an e-mail to someone who is based in Timezone3 and whose OS is configured for that timezone.

I wanted to use a keyboard shortcut to add a signature to the end of my e-mails, as shown above. I therefore created the Bash script listed below, which I named timezone_signature_GeoNames.sh:

#!/bin/bash

location=$(kdialog --title "Current Location" --inputbox "Enter your location:")

localtime=$(perl /home/fitzcarraldo/now1.pl $location)
place=`echo $localtime | cut -d'|' -f1`
place=$place" "`echo $localtime | cut -d'|' -f2`
timezone=`echo $localtime | cut -d'|' -f4`

if [ $location != "" ]; then
  echo -n "Current location: "
  echo $place
  echo -n "Local time now:"
  /usr/sbin/zdump ${timezone} | cut -d' ' -f2-
fi
echo

Notice that the Bash script uses the GUI dialogues utility kdialog to display a pop-up window prompting me to enter the name of a town/city. As I am using KDE I opted to use a dialogues utility developed for use in KDE, but I could have used Zenity instead.

The Perl script now1.pl is a variant of the Perl script now.pl described in my previous post, modified very slightly in order to facilitate formatting of the output by the Bash script, and is listed below.

#!perl

use strict;
use warnings;

use DateTime;
use Geo::GeoNames;
use URI::Escape;
use Encode;

binmode STDOUT, ':encoding(UTF-8)';

my $city = decode("UTF-8", @ARGV ? shift : 'London');
# N.B. Replace London with your home town/city.

my $geo = Geo::GeoNames->new( username => '************' );
# N.B. Replace the asterisks with your GeoNames user name.

my $result = $geo->search(
q       => uri_escape_utf8($city),
maxRows => 1,
style   => 'FULL'
);

defined $result->[0] or die "Unrecognized city '$city'\n";

my $city_name    = $result->[0]->{name};
my $country_name = $result->[0]->{countryName};
my $time_zone    = $result->[0]->{timezone}{content};
my $time_now     = DateTime->now( time_zone => $time_zone );

#print "$city_name ($country_name) $time_now ($time_zone)\n";

print "$city_name|($country_name)|$time_now|$time_zone\n";

exit 0;

The only thing remaining was to configure a keyboard shortcut to launch the Bash script. I opted to use the key combination Ctrl-Alt-z for the shortcut. As I am using KDE I could have used KDE’s ‘System Settings’ > ‘Shortcuts and Gestures’> ‘Custom Shortcuts’ to specify the shortcut and the name of the script it launches. However, as I also use AutoKey for various shortcuts, I opted to use that instead, so I used the AutoKey GUI to create a shortcut named ‘Insert Current Time’ to use the following command:

output = system.exec_command("/home/fitzcarraldo/timezone_signature_GeoNames.sh")
keyboard.send_keys(output)

Use

I compose my e-mails as usual, and, after entering my name at the end of the e-mail, I press Ctrl-Alt-z. A window then pops up prompting me to enter my current location, which I do and then click on ‘OK’. The location and current time at that location are then added to the end of the e-mail, and it just remains for me to click on the ‘Send’ button in the e-mail client’s window. As the Perl script now1.pl uses the Internet to access the GeoNames database, my laptop must be connected to the Internet when I use the shortcut.

KDialog window that pops up when I use the keyboard shortcut

If the town/city name consists of more than one word (Rio de Janeiro, for example) then replace spaces with hyphens when you enter the location name in the pop-up window (Rio-de-Janeiro, for example) and then the keyboard shortcut will return the correct location and local time:

Current location: Rio de Janeiro (Brazil)
Local time now: Fri Oct 16 09:28:19 2015 BRT