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How To: Find Files Owned By A Specific User

In today’s article, we’ll be learning how to find files owned by a specific user. We’ll even use the ‘find’ command, as we find files owned by a specific user! That seems to be the best idea, and the best way to do it.

This should also be a fairly quick article. I don’t see any reason why I’d have to make it longer than it needs to be. So, it won’t take too much of your time today.

This article will be published on November 11. That’s a day known by a number of other names. It’s Veteran’s Day, Armistice Day, Remembrance Day, and probably a dozen more names that I don’t know. It was the day WWI ended, which was thought to be the war to end all wars ’cause it was just that horrific.

Well, as you can see, it was definitely not the last war – but we still choose this day to remember. In the US, veterans are celebrated today. Memorial Day is only for those who are no longer with us. Today is for the vets, as well as those who are no longer here.

It’s a holiday, which means it’s a fine day to have a nice and simple article. It’s a fine day to cherish your friends and family, instead of spending your time online reading Linux articles. (But thanks for doing so!)

Find Files Owned By A Specific User:

This article requires an open terminal, like so very many other articles. 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 terminal now open, you should probably navigate to a directory other than your home directory. If you run this command in your home directory, it’s gonna output a whole lot of text. So, let’s just try this first in your ~/Downloads directory:

cd ~/Downloads

1	cd ~/Downloads

The command we’re going to use is find, and the format is the find command, a dot to say the current directory, the -user flag, and then the username. So, your command would look something like:

find . -user <your_username>

1	find . -user <your_username>

(No brackets, of course.)

You probably don’t have any files owned by root in that directory, so a good test to make sure it’s working properly would be something like:

find . -user root

1	find . -user root

Now, you can mix things up a bit. Instead of using the dot to indicate the current directory, let’s find files owned by root in the /etc directory.

find /etc -user root

1	find /etc -user root

See? That’s not all that hard at all. It’s remarkably easy to find files owned by a specific user – and the command really isn’t that hard to memorize! You can run it in the folder you’re in, or you can use the directory path method.

Closure:

I told you that it’d be a quick article today. It’s a good day for just a quick tip and everyone can benefit from knowing how to find files owned by a specific user. Toss this tip into your growing list of tools in your Linux toolbox, because you never know when this will come in handy.

Thanks for reading! If you want to help, or if the site has helped you, you can donate, register to help, write an article, or buy inexpensive hosting to start your own site. If you scroll down, you can sign up for the newsletter, vote for the article, and comment.

Fix Terminal Command Mistakes

In today’s article, we’re going to cover how to fix terminal command mistakes. While this may sound complicated, it’s actually very easy. As such, it should be a pretty short article. There’s not a lot to it, so it’s not hard to cover.

When you type a command in bash using systems, the command gets saved to the ~/.bash_history file. You can then use the up arrow and use that command again without having to type it again. We’ve also covered how to delete a ~/.bash_history entry. There have been a few articles on this subject.

So, with all that, this shouldn’t be a completely foreign article. It should be something that’s more or less familiar to new people and my regular readers. Because of this, it’s going to be a pretty short article.

Amusingly, it’s not that I want to write an easy/short article today, it’s just that this topic isn’t all that complicated. I was perfectly willing to write a longer article.

So then, let’s have a short article! Let’s learn how to…

Fix Terminal Command Mistakes:

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 terminal now open, type an incorrect command. For example, you could try entering the following command to change to the ~/Downloads directory:

cds ~/Downloads

1	cds ~/Downloads

As you can guess, that’s likely to throw some sort of error. The command you’re actually intending to type would have been cd ~/Downloads. Well, you can fix it and run it automatically. Try this:

^cds^cd

^cds^cd

Tada! It should correct the previous command and then handily run the command on your behalf. To show you what I mean, here’s an image:

correcting an erroneous terminal command — See? It changes ‘cds’ to ‘cd’ and runs the command on your behalf. Pretty nifty, huh?!?

Yup, it just takes a couple of carets and spelling the proper command. It’s not all that hard to fix terminal mistakes. Just to be clear, bash will store both the original mistaken command and the properly fixed command in your ~/.bash_history. But, you can still use the arrow key to go back to either in the future. Of course, you can always delete the bash history entry if you want.

Closure:

See? It is indeed a short article after all. It’s not all that complicated to fix terminal command mistakes, so it’s easy to cover. It’s that how to fix terminal command mistakes is just not something that many Linux users, especially new users, know they can do. Well, you can – and it’s really simple.

How To: Get CDROM/DVD Information From The Linux Terminal

In today’s article, we’re going to learn how to get CDROM/DVD information from the Linux terminal. What we’ll be doing is getting hardware information. It should be a brief article, as we’re just going to cover two commands.

I won’t even need to detail the various options, as we’re just after the hardware information. I’d say it’s going to be a short article, but that has a way of blowing up in my face and those articles sometimes end up longer than the “regular” articles! You get what you get. If you don’t like it, write an article or two for me!

This particular article is actually based on one of my unix.stackexchange.com answers that didn’t get much notice, even though it was the accepted answer. Frankly, in modern days there’s not much need to know this information, as optical disks become a thing of the past. I decided to place the content here, hoping it’s easier for people using search engines. People still use optical media.

As you may know, most of my traffic comes from search engines. That’s the primary motivation for moving this answer here. I’m also motivated by laziness! I want a nice and easy day, for reasons I’ll probably detail in the next meta article. I also want it more easily indexed.

If you don’t know much about your CDROM/DVD player/recorder, then this would be a good article for you. In fact, even if you do know the basics, this is still probably a good article for you. You can learn a lot with a few simple commands. You’ll see…

So then, let’s learn how to get CDROM/DVD information from the Linux terminal. Sure, there’s probably a GUI way to do this, but let’s just stick to the terminal – after all, every Linux user has a terminal available. Plus, I don’t know a GUI method.

How To: Get CDROM/DVD Information:

In today’s article, we’re going to learn how to get CDROM/DVD information from the Linux terminal. What we’ll be doing is getting hardware information. This will require an open terminal. So, to open a terminal, just press CTRL + ALT + T and your default terminal should open.

With your terminal now open, you may need to install the first application we’ll be using. The first application we’ll be using is ‘wodim’, an application used to write data to an optical disk. If you’re using a major distro, it’s in your default repositories. If you’re using apt, then install it with:

sudo apt install wodim

1	sudo apt install wodim

Of course, adjust that command to suit the distro you’re using, be it yum or even zypper. Then, run the following command:

sudo wodim -prcap

1	sudo wodim -prcap

Consult the output. That’s it. It should be obvious. Also, if you get any errors from this command, along with the second command I’ll share, remove any disks from the drive.

For the second command to find CDROM/DVD information, and cdrecord is more likely to be installed by default, you need only to use this command:

sudo cdrecord -prcap

1	sudo cdrecord -prcap

Note the similar flags. It’s pretty much the same as you’re going to get with wodim, except cdrecord has a chance of being installed already. I don’t think I’ve come across a distro with wodim installed by default, but I could be wrong. I have come across distros with cdrecord installed by default. So, there’s that.

If I’m wrong and a distro exists with wodim installed by default, be sure to yell at me in the comment section! I’ve been wrong before, so this won’t be a first. I’m a big boy, I can handle it! Also, I’m kinda curious, so please do let me know in a comment.

Anyhow, enjoy the output from either command. They’ll tell you a bunch of information about your optical drives. Both of the commands will help you get CDROM/DVD information. Pick the one you like best and run with it. It’s your computer, you do what you want!

Closure:

As you can see, it’s pretty easy to get CDROM/DVD information from the Linux terminal. As you can also see, you have yet another article! There sure have been a lot of ’em. Again, I reach out to see if you’d like to write an article. I sure could use a break! We’ll soon cross the 300 articles mark! I am very grateful to those who have already helped.

How To: Compress And Decompress .bz2 Files

In today’s article, we’re going to discuss how to compress and decompress .bz2 files. This is something you may eventually need to know, so I’ll cover it here. I’ll just cover the basics, as most folks won’t need to know anything more than the basics. This should actually be a fairly short and direct article. There’s not a whole lot to it.

If you don’t already know, .bz2 files are bzip2 files. You’ll find that bzip2 is an opensource compression program that gets some regular usage, and you’ll sometimes find downloaded files that are compressed with this format. You may also, for compatibility reasons, want to compress files with bzip2 to share with other users who are already set on using the .bz2 format.

For the curious, the bzip2 man pages define this particular application as (and, as always, I highly encourage folks to read the man pages themselves – this one being a bit more complicated than others):

bzip2, bunzip2 – a block-sorting file compressor

Again, we’re going to just cover how to compress and decompress .bz2 files in this article. That’s all we’re going to do. You don’t tend to come across too many files compressed with bzip2, but they do show up from time to time.

Because of that, we’re going to cover how to compress and decompress those files in this article. It’s gotta get covered eventually, so it might as well be now. Read on!

Compress And Decompress .bz2 Files:

You might actually not have bzip2 installed. It’s not always installed by default. Fortunately, as far as I can tell, it shares the same name in every major distro, that is ‘bzip2‘. So, just go ahead and install it like you’d install any other software. For example, if you’re using Fedora, your command would look similar to:

sudo dnf install bzip2

1	sudo dnf install bzip2

See? I didn’t use Ubuntu as the default example! We’re mixing everything up today! (Use apt if you’re using a distro with apt, like Debian or Ubuntu and derivatives.)

At this point, you should probably have a .bz2 file to work on for the sake of the article. Seeing as I have no idea what you’ve already downloaded, we should probably start with you making one – just so you can see how to decompress it.

To compress a file with bzip2, the command looks like (See the detailed warning below this command, do not use this command without reading the warning!):

bzip2 -z <file_name>

1	bzip2 -z <file_name>

That will create a file with the same filename but make a .bz2 file. However, this is a destructive act. If you use the above command, the original file will be deleted! If you wish to keep the original file, you need the -k (keep) flag. That looks like:

bzip2 -zk <file_name>

1	bzip2 -zk <file_name>

That command will not remove the original file, as would be the default. Obviously, the -z flag means ‘zip’.

If you want to decompress a file with bzip2, the command looks like:

bzip2 -d <file_name>.bz2

1	bzip2 -d <file_name>.bz2

This will extract the file(s) into the current directory. Of course, the -d means ‘decompress’. This is not a destructive operation. The original and extracted files will remain on your file system.

As you can see, it’s not all that difficult to compress and decompress .bz2 files. You might go years not seeing any files in that format, but you’re eventually going to bump into one and now you know how to deal with it in the terminal – and how to respond in kind.

Closure:

And there you have it. You have yet another article. We’re getting close to 300 articles at this point, so it has been a long journey. If you feel like writing an article, let me know! Anyhow, you can now compress and decompress .bz2 files easily enough, and that was the point of the article.

Some Fun With Sorting The Output Of ‘ls’

Today’s article will be relatively short and easy, as we have some fun with sorting the output of ‘ls’. It’ll be a pretty short and simple article, but that doesn’t mean it’s not useful. Read on and learn about sorting the output of ‘ls’!

The last article I wrote was:

Some Fun With Formatting The Output From ‘ls’

This article will be remarkably similar, but isn’t about formatting the output of ‘ls’, it’s about sorting the output of ‘ls’. Yes, there is a difference! This is useful for a variety of reasons, but it’s mostly useful for viewing your files categorically. There are just a handful of sorting options, but we’ll cover them all.

Like always, it’s important to know that you should not to parse the output of ‘ls’. Parsing the output of ‘ls’ if full of risks, so you shouldn’t do it! The link explains it better than I can, and it tells you what to do instead of parsing the output of ‘ls’.

Obviously, and again, we’ll be using the ‘ls’ command. The ‘ls’ command defines itself fairly accurately as:

ls – list directory contents

So, just like the last article, there’s no real reason to make the intro longer than it needs to be. Let’s just jump right into the article.

Sorting The Output Of ‘ls’:

With your terminal now open, you can stay right there in your /home directory, or you can ‘cd‘ into a directory of your choice – preferably one with a variety of files in it.

When you’re done picking a directory, you have the following choices:

ls --sort=extension
ls --sort=size
ls --sort=time
ls --sort=version
ls --sort=none

ls --sort=extension

ls --sort=size

ls --sort=time

ls --sort=version

ls --sort=none

See? I even alphabetized them for you! The list of what they do should be fairly obvious, with ls --sort=version being the most unusual and only applying to versioned files. Also, while included, there’s not a whole lot of reason to use ls --sort=none, as that’s just the default output.

I find sorting by time to be pretty handy, as well as sorting by size. I don’t have much of a reason to use the rest, but they’re there if you need them. I figured I’d include ’em all, rather than just those that I find useful.

Closure:

There you have it, another short article! It’s also another article about the ‘ls’ command, but this time we’re sorting the output of ‘ls’. I figured I’d do this article right after the other one, mostly so that I’d remember to actually cover it.