glow.li: 2016

Android notifications for Profanity in Termux

Thu, 10 Nov 2016 00:00:00 +0000

Just like with weechat you can now receive Android notifications on Termux when you receive a message in Profanity. I wrote a small plugin to achive exactly that. You can download it from GitHub and install it with /plugins install ./profanity-termux-notification/termuxnotify.py. Read more about the installation requirements and configuration options on GitHub.

Access Termux via USB

Tue, 20 Sep 2016 00:00:00 +0000

I've been using Termux over SSH for quite a while now. I've always done so over WiFi. This works reasonably well at home, where I control the IP Addresses. In other networks it was more annoying, because I always had to run ifconfig first, to get my IP. But the big annoyances start when you want to use it in a place that has no WiFi network available. Previously, I used an Android tablet and a keyboard. With this I set up a WiFi direct connection between my phone. It's wonky and sometimes requires to restart both devices before working again, but it works.

Then I got a laptop. Installed a proper Linux on it and tried to connect to Termux. I tried setting up WiFi Direct. But after an hour or so of messing around wpa_supplicant I concluded that it's just too much of a hassle. But somewhere in the GitHub issues I came across the mention of connecting to Termux via ADB. The ADB shell is bad. I didn't actually manage to launch Termux programs via the ADB shell, but I heard that it's possible. But, and this is the point of this article, you can create port forwarding via ADB. This means that you can map a local port on your computer to a port on your Android device. Then you can open the 8022 port to access Termux via SSH over USB. This is awesome, when you're on the train, in a coffee shop or otherwise in a place with wonky or nonexistent WiFi.

Here is how you do it

1. You need ADB

Most operating systems have an ADB package. On my one I was simply able to install it with:

sudo apt install adb

For other platforms you can check this site here.

2. Create your port forward

This part is really simple as well, and that's key. I don't want to do 500 things every time I want to connect to my phone.

adb forward tcp:8022 tcp:8022

This is really all it takes. The first instance of tcp:8022 is the local port you want to bind the remote port to. The second one is the port from your Android device. Because Termux' SSHD runs on port 8022 by default, this is what you want.

3. Connect to it

Now that your local port is bound to your Android device you can simply connect to localhost on your computer:

ssh localhost -p 8022
#This is were you put the local port
#(ie. the first one)

This will connect you to your SSH Server. If you haven't set this up yet read this.

You will need to run the ADB command after every restart or after you've unplugged your device. I set up an alias for myself for the following command sequence:

adb forward tcp:8022 tcp:8022 && adb forward tcp:8080 tcp:8080&& ssh localhost -p 8022
# This will also setup the port 8080, which is used by the httpd webserver on termux

Pixel fonts in a browser without font smoothing

Fri, 15 Jul 2016 00:00:00 +0000

Tinier is a pretty cool font. It is a so called pixel font, and it is just about the smallest font I could find. The letters can be displayed at a font-size of 4px. This means that each character is only 3 pixels tall.

The wizard quickly jinxed the gnomes before they vaporized.

I think this is pretty cool, so I tried to implement this on my website for the footer blurb. It turns out though, that pixel fonts look absolutely hideous in modern browsers. Here is how it looked:

Do you see these hideous colored pixels? It ruins the pixel font. The footer was originally white on blue, where the problem was even worse:

How it should look: Nice, clean, black on white Pixels.

As with any modern software, browser employ font smoothing. This is done so text looks good on a low DPI screen. It is done with anti aliasing and sub pixel rendering and for normal fonts this is pretty great, but for pixel fonts it looks terrible. There is no way for a font to disable it, so it usually has to be done at a software level. Some browsers have a setting for disabling font smoothing. This is obviously pretty useless, since I can't expect readers of my blog to have turned this off and made all normal fonts look bad except my tiny blurb.

There must be a CSS setting right?

Well, let me tell you about font-smooth. It was present in early drafts of CSS3, but has been removed from the specification since. It only works on some browsers and only on the Mac OSX operating system. So it looks like there is no easy way to implement a pixel font without ugly rendering artifacts.

But why don't you just use an image?

Yes, I could just write my text in GIMP and upload it as a picture. But I want it to be dynamically generatable. I want to do it in good old HTML and CSS.

So I have decided to go the sprite map route instead

Having it as a sprite map has many advantages including (and probably limited to):

You can still wrap text around newlines
You only have to have one image for any size and length of text.
Because the original characters are still in the HTML you can select and copy it

Here is how the HTML of a very short text looks:

<span class="charfont-tinier"><span class="charfont-o">O</span><span class="charfont-l">l</span><span class="charfont-i">i</span></span>

As you can see every letter is just a <span> with a special class and the original letter inside it. And since this is a Jekyll blog, I wrote a short ruby plugin to achieve this, but it would probably work really well in JavaScript as well.

module Jekyll
    class Charfont < Liquid::Tag
        def initialize(tag_name, text, tokens)
            super
            html = "<span class=\"charfont-tinier\">"
            text.upcase.split("").each do |i|
                if i == " "
                    classname="SP"
                elsif i == "."
                    classname="dot"
                else
                    classname=i
                end
                html = html + "<span class=\"charfont"+classname+"\" >" + i + "</span>"
            end
            html = html + "</span>"
            @output=html
        end
        def render(context)
            @output
        end
    end
end
Liquid::Template.register_tag('charfont', Jekyll::Charfont)

And here is the accompanying CSS:

.charfont-tinier span {
    color: transparent;
    background-image: url("../media/images/tinier");
    margin-left: calc(1px * var(--scale));
    display: inline-block;
    background-size: calc(5px * var(--scale));
    width: calc(3px * var(--scale));
    height: calc(4px * var(--scale));
    overflow: hidden;
    background-repeat: no-repeat;
    image-rendering: optimizeSpeed;
    image-rendering: -moz-crisp-edges;
    image-rendering: -o-crisp-edges;
    image-rendering: -webkit-optimize-contrast;
    image-rendering: pixelated;
    image-rendering: optimize-contrast;
    -ms-interpolation-mode: nearest-neighbor
}
.charfont-tinier{
--scale:1;
}
.charfont-big .charfont-tinier{
--scale:5;
}
.charfont-tinier .charfontA {
    background-position: 0px calc(-0px * var(--scale));
}

.charfont-tinier .charfontB {
    background-position: 0px calc(-4px * var(--scale));
}

.charfont-tinier .charfontC {
    background-position: 0px calc(-8px * var(--scale));
}

You can look at the whole CSS file here.

So, this is a very complicated solution to a problem that really should be as simple as font-smooth. And it still isn't prefect. Having it do proper line-wrapping would require a bit more complicated HTML and CSS. Also the image-rendering part doesn't work on all browsers, so when text size is large it would look like this:

Edit:

Since writing this post Chrome has made some changes. It now enforces a minimum font-size of 6px. Therefore my previous method of using em and font-size=1px no longer works. I've updated the code in this post to use a css variable to define scale. This way I can still enlarge the font with CSS.

I am moving on Saturday. There is so little time left but it is still so long until then

Tue, 31 May 2016 19:10:05 +0000

I am moving on Saturday. There is so little time left but it is still so long until then

alias sl="apt install sl>/dev/null >&1; sl; apt remove sl -y >/dev/null 2>&1"

Wed, 13 Apr 2016 16:33:28 +0000

alias sl="apt install sl>/dev/null >&1; sl; apt remove sl -y >/dev/null 2>&1"

Pass variables from Termux to Tasker

Sun, 03 Apr 2016 00:00:00 +0000

I figured out that you can pass variables from Termux to a Tasker task. This example sets Android's volume to a value specified in Termux.

Step 1: Creating the script

volume.sh

#!/data/data/com.termux/files/usr/bin/sh
#am broadcast --user 0 -a net.dinglish.tasker.[task name] -e [variable name] "[value]" > /dev/null
am broadcast --user 0 -a net.dinglish.tasker.volume -e volume "$1" > /dev/null

Step 2: Create a Tasker profile

Create a new profile
Choose "Event"
In the "Select Event Category" dialog choose "System"->"Intent Received"
As Action define net.dinglish.tasker.volume

This profile will now be called whenever it receives the "volume" intent.

Step 3: Create the Task

Tap "New Task" and give it a name
Tap + to add a new Action
Choose "Audio"->"Media Volume"
Under "Level" tap the icon with the crossing arrows to switch to text mode.
Enter %volume as a value
You need to exit Tasker for the changes to take effect.

Step 4: Run the script

You can now run the script. It will send an intent to Tasker. It will put the first argument as new volume, which has to be an integer from 0-15.

./volume.sh 4

This is only a simple example of what you can do with variables. Let me know what you come up with.

Display output of a bash script on a widget

Tue, 16 Feb 2016 00:01:00 +0000

I managed to build a bridge between Termux and Minimalistic Text using Tasker. I use it to display the last 20 lines of the #termux irc channel as you can see in the picture. I've done it without having Tasker check a file every two minutes. The Task is directly called from the script.

This tutorial is not Termux specific and should work with any terminal emulator

Step 1: Creating the script

All you have to do is write your output to a file in /sdcard/. In this example I am grabbing the last 20 lines of log of the #termux irc channel from my server.

while true; do
  # You can basically add your own commands here. They just have to write
  # their output to `/sdcard/widget`

  # For maximum battery and bandwidth efficiency tail and cut are
  # executed on the server
  # the cut command removes the timestamps
  #
  # for this to work you need to have placed your public key on the server.
  # Otherwise you will need to enter your password every two minutes
  ssh user@example.com "cat ~/.weechat/logs/irc.freenode.#termux.weechatlog |tail -n 20 | cut -c 21-">/sdcard/widget

  # This sends an Intent. This is how we'll call the Tasker task which
  # updates the widget. "net.dinglish.tasker" has to be there every
  # time for tasker to receive the intent. The last part is the name
  # of the intent which you can change if you want more than one.
  # This normally produces a bit of useless output. I am removing #
  #that with `>/dev/null`
  am broadcast -a net.dinglish.tasker.updatewidget --user 0 >/dev/null

  # sleep for 120 seconds. How often it should update the widget.
  sleep 120
done

If you run this it will download the last 20 lines of the log from a server, paste it into /sdcard/widget and call Tasker with an Intent.

You should also create the file /sdcard/widget now. Simply do touch /sdcard/widget. { .right}

Step 2: Create a Tasker profile

Create a new profile
Choose "Event"
In the "Select Event Category" dialog choose "System"->"Intent Received"
As Action define net.dinglish.tasker.updatewidget

This profile will now be called whenever it recieves the "updatewidget" intent. This is a usefull way to extend the functionality of Termux. I also use it to kick of some Foldersync jobs from the terminal.

Step 3: Create the Task

Tap "New Task" and give it a name
Tap + to add a new Action
Choose "File"->"Read File"
Tap 🔍 and choose /sdcard/widget.
Under "To Var" enter %Widget
Tap + again to add another new Action
Choose "Plugin"->"Minimalistic Text"->"Minimalistic Text"
Click the pen to edit the configuration
Enter %Widget for both variable name and variable content

Step 4: Configure Minimalistic Text

Add a Minimalistic Text widget to your homescreen
Choose any preset
In the "layout" tab remove remove all rows. Now you have a blank widget
Add a new element with +
Switch "Misc" Tab and tick "Locale variable"
Tap "OK"
Click on the new "Locale variable" element
In the popup enter %Widget as a the "Variable name"
"OK" and Save

Step 5: Run the script

Now you can run the script in Termux. Your widget should get updated right away.

Use your current location for wego in Termux

Tue, 16 Feb 2016 00:00:00 +0000

Wego is a pretty cool weather client for the terminal.

You also need termux-api and the jq package.

Now you can run the following command to display the weather report for your current location.

loc=$(termux-location -p network)&&wego "$(echo $loc | jq .latitude),$(echo $loc | jq .longitude)"

Wego on termux

For wego to work you must set the WEGORC environment variable. You probably want to do this in your shells startup script.

export WEGORC=$HOME/.wegorc

Otherwise it installs just fine if you follow the instructions.

Wttr.in

If you don't want to go through the hassle of installing wego, you can just use wttr.in instead. Wttr.in is an implementation of wego that can be called with just curl wttr.in to get the current weather. If you don't want to rely on IP Geo location you can also use the same script for wttr.in instead of wego.

loc=$(termux-location -p network)&&curl wttr.in/$(echo $loc | jq .latitude),$(echo $loc | jq .longitude)

Carpaccio really isn't as fancy when it comes in a plastic tray.

Thu, 21 Jan 2016 17:21:27 +0000

Carpaccio really isn't as fancy when it comes in a plastic tray.

I have a really big scarf.

Thu, 21 Jan 2016 06:59:43 +0000

I have a really big scarf.

Compile aclock on Termux

Sun, 17 Jan 2016 00:00:00 +0000

Aclock is a another clock program, but this time it's an analog clock.

To compile it on Termux you'll need to downloaded the source.

wget https://raw.githubusercontent.com/tenox7/aclock/master/sources/aclock-unix-curses.c

You'll also need the ncurses-dev package.

apt install ncurses-dev

Now you simply have to compile it.

gcc aclock-unix-curses.c -o aclock -lncurses -lm

After that you can simply run it with ./aclock.

Compile Stag on Termux

Sat, 16 Jan 2016 00:00:00 +0000

This post is now obsolete. You can install stag from the repository.

Stag is a cool little programm that generates a bar graph.

To compile it on Termux you'll need to downloaded the sources from GitHub.

git clone https://github.com/seenaburns/stag.git

To compile you need to install the ncurses-dev package.

apt install ncurses-dev

Open the stag.c file and change line 90 from char opt to signed char opt, otherwise it will throw an error during compilation. You'll also need to make a change to the Makefile, so that the right compiler is used. Change line 1 from CC ?= gcc to cc = gcc. After that you can simply use make to compile and install it.

make
make install

Examples

CPU usage statisitc

while true; do top -bn1 | grep "CPU:" -m 1 | cut -f1 -d"." | cut -f2 -d" " ;sleep 1; done | stag -t "CPU"

Android battery status

while true; do termux-battery-status | jq .percentage;sleep 60; done | stag -t "Battery Stats"

Compile tty-clock on Termux

Sat, 16 Jan 2016 00:00:00 +0000

This post is now obsolete. You can install tty-clock from the repository.

Tty-clock is a small program that displays a digital clock.

To compile it on Termux you'll need to download the sources from GitHub.

git clone https://github.com/xorg62/tty-clock.git

You'll also need the ncurses-dev package.

apt install ncurses-dev

Sadly, compiling with make doesn't really work with this one, I managed to compile it with the following command.

gcc -Wall -Werror -Wextra -std=c99 -pedantic -Wno-unused-parameter -lncurses -o tty-clock ttyclock.c

You can then install it with make install.

My blog now also runs on Jekyll. Can I sit at the cool kids table now?

Thu, 07 Jan 2016 16:11:52 +0000

My blog now also runs on Jekyll. Can I sit at the cool kids table now?

Android notifications for WeeChat in Termux

Tue, 05 Jan 2016 12:30:59 +0000

I figured out how to have WeeChat in Termux create a notification on your android device whenever someone mentions your username or you receive a private message.

You need to have Termux:API installed for this. All you need to do is type following command into WeeChat:

/set trigger.trigger.beep.command "/print -beep;/exec -bg termux-notification -t 'IRC Notification' -c "${tg_tag_nick}: ${tg_message_nocolor}";/exec -bg termux-vibrate"

Explanation

Normal WeeChat behavior is to send a BEL character to the terminal whenever someone mentions you or sends you a private message. This extends that with the commands termux-notification and termux-vibrate found in the Termux:API. The content of the notification is ${tg_tag_nick} (which is the user who sent you the message) and ${tg_message_nocolor} (which is the message without coloring). Here you can find more available variables.