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Short: Automatically Add An Extension To Multiple Files In The Linux Terminal

This short article will have limited usage as it shows how to automatically add an extension to multiple files in the Linux terminal. This is something not everyone needs to know, but something you need to know if you need to know it.

Let me explain…

First, I wrote a snippet of terminal code to help out a forum user. I decided that it was valuable enough to share with the larger world. As it’s just a snippet, it can be a short article.

In this case, the user had recovered many images and the recovered file names did not have a .jpg extension. They were going to manually edit a thousand files to add the .jpg extension. That’s not something you need to do. You can automatically add an extension to multiple files in the Linux terminal.

So, how does this work…

Automatically Add An Extension To Multiple Files:

Open your terminal and navigate to the appropriate directory. You can usually use your GUI file manager to navigate to the directory and then open the directory from that window. Otherwise, just use the cd command to navigate to the right directory.

The syntax to add the extension to all those files in that directory would be:

rename 's/$/.<extension>/' *

1	rename 's/$/.<extension>/' *

What we’re doing is using the rename command to search for anything with zero to one character and the asterisk is all characters including spaces. You should have rename available by default. I first tried using an asterisk in both places, but the command was having none of it.

If you want to test this, open your terminal and try this:

mkdir temp
cd temp
touch foo bar foobar barfoo bar1 foo1 foobar1
ls

mkdir temp

cd temp

touch foo bar foobar barfoo bar1 foo1 foobar1

That should show you the newly created files.

Next, just run:

rename 's/$/.jpg/' *

1	rename 's/$/.jpg/' *

Now confirm that you’ve made the changes:

ls

Your output should match this one:

$ ls
bar1.jpg  barfoo.jpg  bar.jpg  foo1.jpg  foobar1.jpg  foobar.jpg  foo.jpg

1 2	$ ls bar1.jpg barfoo.jpg bar.jpg foo1.jpg foobar1.jpg foobar.jpg foo.jpg

See? You’ll have added .jpg to all the files in that directory. We could use something like the find command and make it recursive, but this is good enough.

Closure:

There you have it. You have a short article that will show you how to add an extension to multiple file types. I figured this was useful enough to be shared with the wider world, maybe saving someone a bit of time and showing others how easily you can process things in the Linux terminal.

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Set Individual Flatpaks Permissions With Flatseal

This will be an article about Flatpaks permissions and how you can set said Flatpaks permissions with Flatseal. There’s a good chance that this will be a relatively short article, which is nice.

BEFORE YOU BEGIN:

I covered what a Flatpak is and some other bits of information. Read this:

Install Flatpaks In Lubuntu

That will give you an overview and enough information to get started. The only thing that will change is how you enable Flatpak and the Flathub repository. The method you use to do that will be different unless you’re using a distro that relies on the apt package manager.

What Is Flatpak:

I wrote this information out already, but some of you will not bother clicking immediately so I’ll mention that a Flatpak is an application that runs with its own dependencies and is sandboxed from the rest of the system.

The important part of this is that the developers who packaged the Flatpak set the permissions for that application. For example, their application may need access to the network. Their application may need access to storage media. The Flatpak may need to be able to access the sound manager so that you can hear things output by the application.

Well, you can adjust those permissions. If you want to grant additional access, you can do that. If you don’t need certain features, you can deny access to those resources. It’s up to you.

The developer shipped the Flatpak with a set of permissions. There are also default permissions that you can edit. If you want to do something like disallow all Flatpak access to the network, you could do that. You can also adjust these permissions on a per-application basis.

Which leads us to this…

Set Flatpaks permissions with Flatseal:

If you want to manage Flatpaks permissions with Flatseal, you can start (and pretty much close this page) with the following link:

Flatseal on Flathub

The installation instructions will be available on that page. Alternatively, if you’ve already enabled Flatpaks (see the earlier link in this article) you can just press CTRL + ALT + T to open your terminal and enter the following command:

flatpak install flathub com.github.tchx84.Flatseal

1	flatpak install flathub com.github.tchx84.Flatseal

After you enter that into your terminal, you’ll press the Y button on your keyboard a couple of times to confirm that you wish to install.

With that said and done, you can then open your application menu, find Flatseal, and open the application. I’ll give you a screenshot, but there’s just so much more to this application that I can’t cover it. It’s fairly self-explanatory and you should be able to figure it out – but there are many options.

Flatseal is used to adjust the permissions of a Flatpak. — That’s just the tip of the iceberg. Scroll down and there are maybe 50 options. Good luck!

There are just too many options for me to cover. The best way for you to learn how to use Flatseal is to simply install Flatseal and examine the options. If you have any questions about those options, reach out and I may be able to help. Otherwise, you can figure this out on your own.

I have faith in you. You can figure this one out!

Closure:

Well, you can now adjust Flatpaks permissions with Flatseal. I’m never quite sure how to pluralize or make it possessive, but I did my best. We’ll have to see how the final article does.

Anyhow, I told you this should be a fairly short article. It’s not designated as a short article because it’s a bit long for that and you have to read a bunch of other stuff if you want to use this as your starting point. If I could assume you had Flatpaks already enabled, this could have been a short article. I’ll make no such assumptions.

Test Your Storage Drive’s Read Speed

One of the most frequent things you’ll do is read data from disk, so why not test your storage drive’s read speed? In this article, we’ll use an application we’ve used before. This shouldn’t be a very complicated article.

We store data on drives, or disks if you prefer. Most of us don’t use disks as our main storage devices. We do use disks for backups or storing large amounts of data, but we largely use SSDs these days. Some of us even use NVMe M.2 SSDs to store our data. The latter is currently the quickest you’re likely to encounter as a consumer.

The old spinning platters we used (though we’ve used lots of forms of magnetic storage) are typically referred to as HDDs (Hard Disk Drives). The SSDs (Solid State Drives) have no moving parts and are much faster. The NVMe M.2 SSDs are faster still.

If you’re suffering from some bottleneck, you might want to diagnose that. You might just be curious. It is also possible that you just purchased new hardware and want to see if the storage device reaches the advertised speed.

The tool we’ll be using is hdparm. This works fine with USB thumb drives, HDDs, regular SSDs, and even NVMe SSDs. It’s a complex application with a lot of options. I’ve covered some features before.

How To: Show Your Hard Drive Specifications In The Terminal

So then, let’s learn about this hdparm…

hdparm:

It should be noted that this hdparm application should be installed by default. It should also be mentioned that hdparm is a terminal-based application. You can verify that hdparm is installed with the following command:

which hdparm

1	which hdparm

If you then check the man page (with man hdparm) you’ll see that hdparm is described quite nicely like this:

hdparm – get/set SATA/IDE device parameters

If hdparm is not installed, you can surely find it in your package manager.

As you can see, hdparm is the right tool for the job assuming you want to test your storage drive’s read speed. It’s also the right tool for a bunch of other jobs, but we’ll just be covering the read speed today.

Test Your Storage Drive’s Read Speed:

As I mentioned above, this hdparm application is something you use in your terminal. I suspect my regular readers will have guessed that. If you’re new to the terminal, more often than not you can open your default terminal by pressing CTRL + ALT + T.

With your terminal open, let’s identify your storage drives with this command:

df

You’re interested in the bits that start with /dev/<drive_ID> as those are the drives you’ll be able to test.

NOTE: You should run these tests several times and average them, and you should do so while the system is otherwise idle. That will give you the peak results.

We’re interested in two flags, as they represent two tests. The -t flag tests the read cached. The -T flag tests the drive’s buffered read timings. You’ll often find the first test is fairly similar throughout the different drives and that the cached test shows the most differences. If those two terms, cached and buffered, confuse you, here’s a link about the differences between cache and buffer as far as the hdparm application goes.

You’ll need elevated permissions for this, so the command looks like this:

sudo hdparm -tT /dev/<device_ID>

1	sudo hdparm -tT /dev/<device_ID>

Or, as an example for many of you, the command might look like this:

sudo hdparm -tT /dev/sda1

1	sudo hdparm -tT /dev/sda1

That command will test both the cached read speed and the buffered read speed. These tests are important because you’re using a smart operating system that puts things into the cache and buffer that are likely to be read from the drive. So, the command listed will test both. You can split them up of course.

I decided to get you some examples:

Some Quick Read Speed Tests:

This is the internal SSD on a desktop:

/dev/sda1:
 Timing cached reads:   16736 MB in  1.98 seconds = 8451.25 MB/sec
 Timing buffered disk reads: 512 MB in  1.10 seconds = 464.39 MB/sec

/dev/sda1:

Timing cached reads: 16736 MB in 1.98 seconds = 8451.25 MB/sec

Timing buffered disk reads: 512 MB in 1.10 seconds = 464.39 MB/sec

Next is a USB 2.0 device plugged into that desktop:

/dev/sdc1:
 Timing cached reads:   16904 MB in  1.98 seconds = 8532.39 MB/sec
 Timing buffered disk reads: 240 MB in  3.01 seconds =  79.74 MB/sec

/dev/sdc1:

Timing cached reads: 16904 MB in 1.98 seconds = 8532.39 MB/sec

Timing buffered disk reads: 240 MB in 3.01 seconds = 79.74 MB/sec

Then we have an external HDD plugged into a USB 2.0 port on that desktop:

/dev/sdb1:
 Timing cached reads:   16548 MB in  1.98 seconds = 8350.55 MB/sec
 Timing buffered disk reads:  62 MB in  3.17 seconds =  19.56 MB/sec

/dev/sdb1:

Timing cached reads: 16548 MB in 1.98 seconds = 8350.55 MB/sec

Timing buffered disk reads: 62 MB in 3.17 seconds = 19.56 MB/sec

For comparison, this is an NVMe M.2 SSD:

/dev/nvme0n1p1:
 Timing cached reads:   29316 MB in  2.00 seconds = 14681.89 MB/sec
 Timing buffered disk reads: 4210 MB in  3.00 seconds = 1403.05 MB/sec

/dev/nvme0n1p1:

Timing cached reads: 29316 MB in 2.00 seconds = 14681.89 MB/sec

Timing buffered disk reads: 4210 MB in 3.00 seconds = 1403.05 MB/sec

As you can see, the internal SSD is quite fast. The thumb drive is the next quickest. This is followed by the external drive that’s just a spinning platter drive.

Then, of course, you can see that the NVMe M.2 SSD is so much faster. That’s not even the fastest SSD out there. There are faster NVMe M.2 SSDs that don’t cost a lot of money. The prices have come down these days. You can even get a PCIe card that lets you mount an NVMe M.2 SSD if your motherboard doesn’t already support it.

Closure:

Should you want to get some drive benchmarks, you can certainly use hdparm to test your storage drive’s read speed. This isn’t something complicated and most anyone can figure it out. All you need to do is follow the directions carefully and in order. I do try to explain things as I go along.

There’s a lot more to the hdparm application. I encourage you to check the man page. There are probably another half-dozen articles that can be written about hdparm, so you’ll likely see this application again in the future. I doubt I’ll do another one too soon, as I like to space things out and not get too repetitive.

Install Flatpaks In Lubuntu

This shouldn’t be a very long article and will apply to other distros, but this is how you install Flatpaks in Lubuntu. This seems like a good article to write as it’s something tucked into my notes and something I’ve not written about before.

This article applies to Lubuntu. It may apply to other distros, especially those in the Lubuntu family. In some cases, such as Linux Mint, recent versions come with Flatpak support. In those cases, you don’t need to do anything special, you can start using Flatpaks as soon as you’d like.

What Are Flatpaks:

Flatpak is a utility for software deployment. It was once known as xdg-app but has used the Flatpak name for going on a decade. This is not something new, even though it has recently grown in popularity. They’re pretty handy.

The thing that makes Flatpaks special is that they run in a sandbox. That means they don’t interact with other software on your system, they run in their own isolated memory space. This is good for security.

They’re also good for easy installation. Not only do they run in an isolated environment, they are self-contained. With Flatpak being what it is, you don’t have to worry about dependencies.

If a Flatpak does need to integrate with the system, this will be set by the developer. The advanced user can change those permissions, though that may cause breakage should you restrict the access levels.

There’s also a central repository that you can use. While you can get a Flatpak from anywhere, and you can add your own repositories, the most common use will be from a central repository which does things like providing updates to the packaged software.

This is good for developers who want to distribute their software while not having to do so for the various package managers. Rather than a .deb or .rpm version, they can upload and update a Flatpak that’s stored in a centralized repository.

Pretty neat!

Install Flatpaks In Lubuntu:

For the sake of this article, Flatpak is the software type and the delivery mechanism, while Flatpaks are the applications installed via Flatpak. Make sense? I hope so because that’s what I’ve got.

I should probably have mentioned that earlier in the article…

Anyhow, to install Flatpak you’ll need an open terminal. As you’re using Lubuntu, you can open your default terminal by pressing CTRL + ALT + T on your keyboard.

With your terminal now open, let’s install Flatpak so that you can install all the Flatpaks your heart desires. To do that, run this command to install Flatpak:

sudo apt install flatpak

1	sudo apt install flatpak

That will install Flatpak, but you will then want to enable the Flatpak repository. That’s another easy command that you can cut and paste:

flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo

1	flatpak remote-add --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo

Next, you’ll need to reboot. Yes, this one should have a reboot to work properly. Run this command in the terminal:

reboot

reboot

That’s all you need to do.

Installing Flatpaks:

Now you have enabled Flatpak and you’ve added the default Flatpak repository. You can head to the centralized repository and start browsing for interesting software. You do that here:

Flathub, the Flatpak Repository

I’ll give you an example, to make it easier…

Let’s say you want to install ONLYOFFICE as a Flatpak.

Well, you browse/search for it and end up at the ONLYOFFICE repo page.

Once you’re there, you’ll see an “Install” option in the upper right section of the page. There’s a down-arrow next to it, which is the easiest method. Click that and run the command prompt in your terminal.

In this case, that command prompt would be:

flatpak install flathub org.onlyoffice.desktopeditors

1	flatpak install flathub org.onlyoffice.desktopeditors

You can then run the application with this command:

flatpak run org.onlyoffice.desktopeditors

1	flatpak run org.onlyoffice.desktopeditors

No, you shouldn’t need to run the program through the terminal. Because you rebooted, added Flatpaks should appear in your application menu in the appropriate category section.

Also, it’s a bit more of an interactive process when you’re installing Flatpaks through the terminal. You’ll be given a few options along the way, though I just accept the defaults (by pressing the Y key) and call it good.

You’ll also notice that the applications are much larger. If you have slower internet, you’ll notice this. This is because the Flatpaks are isolated and come with the required dependencies. Because of this, the packages are quite a bit larger.

Once in a while, I’ve noticed that the application won’t appear until a reboot happens. If you run the terminal command once, that seems to help it, and then appears in the application menu. It’s not perfect, at least not here, but it’s definitely ‘good enough’ and it’s a great way to get sandboxed software that doesn’t require hunting around for dependencies.

Closure:

So, that’s how you install Flatpaks in Lubuntu. It’s also probably how you install Flatpaks in ElementaryOS, Kubuntu, Xubuntu, etc… However, if you’re installing Flatpaks in Ubuntu there’s an extra step you can take that lets you integrate Flatpaks better with the GNOME desktop environment.

If you’re using Ubuntu, you can add this command before the reboot step:

sudo apt install gnome-software-plugin-flatpak

1	sudo apt install gnome-software-plugin-flatpak

I believe that will add Flatpaks to your regular software store, that is the GUI one where you’d go to add software. I’m not sure because I don’t use Ubuntu, but that’s what the command looks like it will do. I’d normally not share any code I haven’t used myself, but I took the command from Flatpak’s site, which makes me think it’s correct.

Anyhow, Flatpaks are easy to install and run more securely. If your OS changes underneath, this won’t matter. The software comes with the appropriate dependencies. Once you’re more familiar with the software, you can change the permissions if you want. I’ve yet to find a single reason why I’d want to modify the permissions – but it’s possible.

Short: Clear Linux Mint Notifications

This is another short article, as I continue exploring the format, and is simply about how to clear Linux Mint notifications. You can do so graphically, or you can do so with a keyboard.

I should be specific. This is for Linux Mint Cinnamon Edition.

When you get an email, when you have a notice from your email client, or have scheduled some system prompt, you might get a notification. These notifications show up in your system tray.

They look like this:

Notifications from Linux Mint. — See? I even drew an arrow for you! In this case, there are three!

These notifications show up with regularity if you have a lot of email accounts that get constant notifications. They may show up for other reasons.

If you want to use a GUI, just click the notification icon and clear it. That’d look like this image below, and it’s nice and simple:

you can use a GUI to clear notifications from Linux Mint. — This is probably how most of you will clear notifications from Linux Mint.

On the other hand, if you’re pretty sure there are no notifications worth reading, you can always just clear them out with the keyboard.

Clear Linux Mint Notifications With The Keyboard:

If you want to clear Linux Mint notifications with the keyboard, it’s remarkably simple. It isn’t made clear, thus you get this short-form article.

To clear those notifications you simply press the following:

SHIFT + SUPER + C

Now, if you’re unsure, the ‘Super’ key is often labeled to be the ‘Windows Key’. It may say ‘WIN’ on it or it may have the Windows logo emblazoned on it. With your ‘standard’ US keyboard layout, it’s the key on the left between the CTRL and ALT keys.

This could, on Apple keyboards, also be labeled as the CMD key.

But, the ‘super key’ came first. It was an MIT (GO BEAVERS!) thing. If you don’t have anything better to do, read about the Super Key on Wikipedia. The WinKey and CMD key came later in life.

Anyhow, now you can clear Linux Mint Notifications with your keyboard!

Closure:

I’m not sure if I like this short format. I normally have quite a bit to say, even if it’s mundane. There’s a lot to be said about the tools we use. At the same time, there are plenty of meaningful tips that just don’t warrant writing a full article.

So far, exactly one person has opined on the matter and they claimed to like the short articles. A few days later, they also offered the opinion that they liked the longer articles. Given their comments, I’m going to have to assume they also like the regular articles and just like my articles. I’m okay with that, but it’s not exactly information I can act on other than to just keep doing what I’ve been doing.