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How To: Clear The Terminal Screen

Today, we’re going to learn to clear the terminal screen. This is generally done for privacy’s sake. You don’t want people to be able to scroll up and see what you’ve been reading in the terminal. This probably isn’t as important if you’re the only user and you’re in your house, but you may still like to keep things clean and tidy.

We’ll go ahead and cover two ways to clear the terminal in this article. They’re both rather easy commands and you’ll find this article is definitely not all that complicated, or even very long. This is pretty much one of the first things folks should have learned when they started using the terminal. We might as well cover it here.

Rather than make this long-winded, we’ll just make this into a short and easy article to read. Let’s all learn how to…

Clear The Terminal:

To be clear, this just erases the text in the terminal. It clears the scrollback content so that folks can’t scroll up and see the previous terminal contents. Again, it’s a good idea to do if you’re in a multi-user environment where people may have access to your screen and you don’t want them to know what has been written to the terminal.

Obviously, you need a terminal for this article. Just press CTRL + ALT + T and your default terminal should open.

I suppose we’ll need some content, so let’s try using this command:

ls -la

ls -la

That should fill your terminal up.

Now, to clear it you can use either of the two following commands:

clear

clear

Or you can also use:

reset

reset

(Though reset may leave a little text at the top, it still removes the terminal’s scrollback history.)

Both of those will do the job, with ‘clear’ being the obvious winner = but it’s nice to have options. They’ll clear the scrollback in the terminal, preventing folks from scrolling up to read what has previously been written there. Of course, they could potentially still press the arrow up button and see what commands you’ve written, so you can try to prevent that as well.

Closure:

See? I told you that it’d be a quick and easy article. It’s not all that taxing to learn how to clear your terminal and that’s all that this article is meant to cover. Both of the two commands have a man page, but they’re not very useful commands for anything else but clearing the terminal. Have an easy day, a day where you can (maybe) say you learned something and not have to read a long article. After all, it was a quick and easy day for me!

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More Ways To Generate Strong Passwords In Linux

In today’s article, we’re going to explore a couple of other ways to generate strong passwords in Linux. It’s going to be a pretty easy task and one most everyone can learn from. It shouldn’t even be a very long article.

Weak passwords are easy to crack. You don’t want that, for obvious reasons. If you want to see how approximately how long it’ll take to brute force passwords, you can check sites like this one. Remember that the time given by that is more or less the maximum time it could take, and your password could be brute-forced (by repeated guessing) much sooner than that.

I’ve previously written an article about generating a sufficiently complex password. That’d be one way to generate strong passwords, but this article will cover a couple of other easy ways to generate strong passwords in the Linux terminal.

Generate Strong Passwords:

This article requires an open terminal, like many other articles on this site. If you don’t know how to open the terminal, you can do so with your keyboard – just press CTRL + ALT + T and your default terminal should open.

With your password open, we’re first going to use GPG to create a strong password. Everyone should already have GPG installed, so there’s no reason to cover that in this article. So, to do so, you’d use a command something like this:

gpg --gen-random --armor 1 16

1	gpg --gen-random --armor 1 16

It’ll have an output similar to this one:

using gpg to generate a strong password — Obviously, you don’t want to use that password specifically! Use your own!

You can change the 16 to any length you want. It’s obviously the number of characters.

You can also use OpenSSL, which you likely have installed, to generate a complex password. It’s actually pretty easy and the command is:

openssl rand -base64 24

1	openssl rand -base64 24

Again, you can change the 24 to anything you darned well please. Sometimes sites will have a maximum password length, which might seem kinda silly – as I think I recall there being a hard limit of 256 characters that the kernel will accept. Either way, the output would be similar to this one:

openssl can generate passwords too — That one is 24 characters long. Yay!

Feel free to mess around with changing the length. OpenSSL is likely installed by default and you don’t have to install pwgen. Both of the tools in this article will likely be installed by default.

Closure:

And there you have it! Another article said and done. This one is about teaching folks how to generate strong passwords in Linux. It’s an easy enough task and this article shouldn’t be too complicated for even the most n00b of the n00bs!

Kill Frozen Applications The Easy Way

Linux is an operating system and, like every operating system, you sometimes need to kill frozen applications. Computers are not now, nor will they ever be, perfect devices with perfect software. Sometimes, crap happens and you find yourself in a situation where you need to kill a frozen application or two. (Even if it were perfect, your RAM is bombarded with EMR and will eventually knock a bit loose, even with ECC RAM.)

There are all sorts of ways to deal with frozen applications. You can do everything from sigterm to pkill. Worst case scenario, you always have RIESUB to fall back on – for a completely frozen system. All of those are great and have their place, as does this method.

As this is meant to be quick and simple, so we’re just going to jump into it – and have a relatively brief article today.,,

Kill Frozen Applications:

Let’s say you’ve somehow managed to make your browser freeze. It is unresponsive, though the rest of the system seems to work just fine. You could open a terminal and try the pkill and sigterm types of resolutions or you can use xkill. It’s literally point and click!

So, open your terminal and enter the following (read the rest before doing this):

xkill

xkill

When you do, your terminal will look a little like this:

Your cursor might also change. In one test my cursor is an X and on another test, with a different OS, it’s a red skull and crossbones. I couldn’t caputer either in a screenshot, so you get what you get.

NOTE: If you change your mind and don’t want to click-to-close, you can still type in the terminal. You can use sudo pkill <terminal-name> to get back to normal.

Anyhow, take that cursor and click on the application you want to close. This sends a shutdown command to the frozen process and things should go back to normal after the frozen application closes. Of course, sending the shutdown command to a process in no way indicates a certainty of it listening, it may still fail and stay frozen – perhaps depending on how exactly frozen the application is.

NOTE: It has come to my attention that I should warn you. If you click on it after typing xkill, it WILL close it. It’s pretty indiscriminate. It doesn’t care if you’ve saved. It will kill it. I’m also told that CTRL + ALT + ESC is a shortcut in Mint for this, but I can’t seem to make it work.

Closure:

See? I told you that it’d be a quick and easy article. This one is about you you can kill frozen applications – but there are all sorts of ways to do that. You can expect future articles to cover this very subject, but with different methods. I just figured this would be quick and easy for everyone.

How To: Change Ubuntu Into Lubuntu

Today’s article is going to teach you how to change Ubuntu into Lubuntu. Why? Because you can! Because you might want to try a different desktop environment, or because you’d like to have them both on one computer. It’s remarkably easy to change Ubuntu into Lubuntu – and, of course, would work with other official Ubuntu flavors with just slight modifications

As you know, Ubuntu is a distro. Lubuntu is also Ubuntu, but it is an official flavor of Ubuntu. They are not actually different distros. Lubuntu is Ubuntu, with different Ubuntu software installed to provide a different experience.

Ubuntu is Canonical’s flagship operating system. It ships with a suite of useful software and uses the GNOME desktop environment. If you say Ubuntu, that’s the distro you’re talking about. Lubuntu is a separate project under the same umbrella, based on Ubuntu. Lubuntu, once known for being lightweight, is now using the LXQt desktop environment where it once used LXDE. The latter dropped for the former for a whole host of reasons, including maintenance improvements. Comparatively speaking, it’s still fairly lightweight.

Full Disclosure: I’m an “Official Lubuntu Member” and, by extension, also an Official Ubuntu Member. I’m quite biased with regards to Lubuntu, but my biases are open and I still strive to be objective (or at least not objectionable!).

So, if you have Ubuntu installed and you’d like to experience Lubuntu, then this is the article for you, as it will teach you how to …

Change Ubuntu Into Lubuntu:

Like oh so many articles, if you want to change Ubuntu into Lubuntu, you’re going to want to start off with an open terminal. You can use your menu to open a terminal, or you can just press CTRL + ALT + T and your default terminal should open.

Once you have your terminal open, you need to enter just one command, really. The command you’ll enter is:

sudo apt install lubuntu-desktop -y

1	sudo apt install lubuntu-desktop -y

That will run its course and then pause on a screen where you can read about your display manager. There are no real options on that page, so you can just press the enter button after reading it.

This won’t actually take all that long. When you’re done, you can logout and then login to Lubuntu or, more effectively, just reboot and you’ll boot into the Lubuntu environment.

When you reach your new login menu, you can pick which desktop session you want to login with by using the dropdown menu in the upper left, with Lubuntu being the new default. Of course, you can login to the regular Ubuntu session still (as well as Ubuntu on Wayland). Most things will still work in when you’re logged into an Ubuntu session, except for blanking the screen. That fails because you’re no longer using GNOME-display-manager (GDM3). (You’re now using SDDM.)

That was it. That’s all you have to do. However, if you don’t like it and want to change it back, it’s slightly more complicated – but not terribly so – to reverse this change. To reverse it, you need to …

Change Lubuntu Into Ubuntu:

Once again, open your terminal. It’s not hard, as described in the 2nd section of this article. Heck, it’s described in almost every article.

You can start with just this command:

sudo apt remove lubuntu-desktop -y

1	sudo apt remove lubuntu-desktop -y

And that’ll get you almost all the way back to normal. You’ll still have the splash screen and boot logos that belong to Lubuntu. You could leave those and learn to accept them, or you can fully restore the original setup.

Assuming you want things back the way they were, we need to get your display manager reconfigured – restored to what it was. That’s a very easy command. It looks like:

sudo dpkg-reconfigure gdm3

1	sudo dpkg-reconfigure gdm3

You’ll get another one of those warning screens and, once again, there are no options. The only thing you can do is press the enter button. Fortunately, that’s exactly the button you want to press!

Finally, you need to change the boot screens. It’s a pretty easy command, but it is interactive. Just run this to get it started:

sudo update-alternatives --config default.plymouth

1	sudo update-alternatives --config default.plymouth

That will ask you which theme you want to use. In this case, you’ll pick 1 and press the enter key. Basically, you want the option that isn’t “Lubuntu” and this will fix the final visual issue.

When you next reboot, you’ll have the default Ubuntu logo and theme during the whole boot process (assuming everything went as expected). Your login theme will have been restored to Ubuntu’s default, as will have the Ubuntu splash screen while the system boots.

Of course, you could always opt to keep Lubuntu installed alongside Ubuntu, that is LXQt alongside Gnome, if you’d prefer. Then again, if you like your Lubuntu installation, maybe you’ll just want to use it. It’s easy enough to remove GNOME or to even just clean install Lubuntu.

Closure:

And there it is! It’s an article that teaches you how to change Ubuntu into Lubuntu. It’s not a very complicated affair and you can restore it easily enough, should you not like it. You can more or less do this with any other official flavor. Swapping back to just the old Ubuntu will potentially use different commands, but it’ll otherwise be quite similar.

Enable PPAs In Elementary OS

Today’s article will tell you how to enable PPAs in Elementary OS. This is generally considered a bad idea, but it’s your computer and you can do anything you want with it. So, well, this one will have you enabling PPAs in Elementary OS.

I suppose that some folks will have no idea what I’m talking about. So, I’ll point out that Elementary OS is a Linux distro. Also known as eOS, it seems targeted at looking good, having cohesive apps, and charging you money for this. That’s fine. You can use it for free.

Elementary OS is based on Ubuntu, which is based on Debian. Ubuntu has PPAs, a way to install software that’s not in the default repositories, but Debian does not. Some Ubuntu derivatives also do not allow PPAs (by default) and Elementary OS is among those that do not.

Elementary OS developers would prefer you use AppImages or Flatpaks, instead of accepting the security burden that is allowing PPAs. After all, any PPA you add is pretty much like giving someone root access to your computer.

Well, today’s article is about just that. It’s a quick article that’ll teach you how to use PPAs in Elementary OS. Heck, the command to enable this is shorter than this intro, where I show you how to…

Enable PPAs In Elementary OS:

To get started, we’re going to have to have one of those open terminals. You can root through your menu (or use the search feature) or you can just press CTRL + ALT + T and your default terminal should open.

Next, to enable PPAs in Elementary OS, you really only need one command. But, we’ll make sure you’re updated fully before trying this. Thus, you get two commends!

sudo apt update && sudo apt upgrade -y
sudo apt install software-properties-common

1 2	sudo apt update && sudo apt upgrade -y sudo apt install software-properties-common

Now that you’ve done that, you can now add PPAs to eOS. If you wanted to keep up with the more recent versions of LibreOffice, you’d run the following commands:

sudo add-apt-repository ppa:libreoffice/ppa
sudo apt update
sudo apt install libreoffice

sudo add-apt-repository ppa:libreoffice/ppa

sudo apt update

sudo apt install libreoffice

That should install LibreOffice and then keep it updated as the PPA maintainers update the repository. Either way, congratulations! If you’ve done everything correctly, you can now enable PPAs in Elementary OS.

Closure:

There you have it, another article. This article tells you how to enable PPAs in Elementary OS. Their preferences for different packages isn’t too dissimilar than Ubuntu themselves recommending Snap applications. Plus, any PPA you add will the be able to install software by its very nature, Maybe it is time to start doing away with the old ways and moving towards modernity?