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How To: Hide The Output From wget

In today’s article you’re going to learn that you actually can hide the output from wget. I am not one of folks want to do this, but some do. Or at least the option is there, so I assume they do. Either way, read on and you’ll know how to hide the output from wget!

Goodwood Revival is this weekend, but you’ll still get an article. I am thinking about going in person next year, so I’ll have to write articles ahead of time. I probably should have done that even though I’m just streaming it.

Anyhow, there’s an option that will let you hide the output from wget and it’s in my notes. I might as well turn it into an article because I’m sure someone wants to do this.

What this does, to be clear, is shows no wget output in the terminal once you enter the command. You’re not running blind, however. I’ll show you how to at least ensure the command gets completed. So, it does have uses – when you just don’t need to see the clutter.

Lots of people do loads of useful work in the terminal and don’t really need to see clutter, so this is one way to avoid that terminal clutter. I actually prefer to see what’s going on, but I’m weird like that. If you do not prefer to see what’s going on with wget, this article is for you!

Hide The Output From wget:

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.

It next requires that you use wget to get something. So, pick something and download it with wget. I don’t care what. You do you and download anything you want. To hide the output from wget, the command is:

wget -q <file>

1	wget -q <file>

That’s really it. However, you then have no idea if it it completed. Fortunately, you can make sure wget completes its task (within reason) with the -c flag. So then the command would look like:

wget -qc <file>

1	wget -qc <file>

See? Pretty simple. That command will not only hide the output from wget, it will ensure the download is completed. You’ll avoid cluttering up your terminal, or something…

Closure:

There you have it! You now know you can, and how you can, hide the output from wget. You can even be reasonably sure it completes behind the scenes. It’s not a very difficult article to follow today, so consider it an easy day. Now, back to my racing…

Change Your Home Directory

In today’s article you’re going to learn that it’s possible to change your home directory. Why? Because Ol’ David is in a bit of a rush to get this out on time. I can’t miss my publication deadline! So far, there has been an article every other day. Gotta keep up the schedule.

Yesterday was an extremely frustrating day. People managed to waste my entire afternoon. The only consolation I got was that I drove home really quickly, in a very spirited manner. That was not enough consolation. So, I just drank a couple of delicious beers (Sierra Nevada Pale Ale) and went to sleep.

I expected to get up early and write the article. I did wake up early, but I fell back to sleep. My body wanted to catch up on some missed sleep and it did. Which means I’ve got like an hour to write this article.

(I don’t think there has ever been a more ‘bloggy’ post than this one! It’s horrible and I’ll hopefully never do it again.)

When I first planned this article, I planned on showing you how to change your home directory with a new user. It was going to be fairly long and needlessly complicated. So, instead, I’m just going to tell you how to do it. You can learn how to create a new user.

So then, let’s get onto the meat of this…

Change Your Home Directory:

There are all sorts of reasons why you might want to change your home directory. Maybe you don’t want people being able to easily spot it by traversing your directory tree? You might want to move it to a different partition that has more space? Who knows?

But, this isn’t something you want to do willy-nilly. See, a whole lot of things depend on your home directory and your home directory probably contains a lot of stuff. So, after you’ve changed your home directory you’re probably going to need to move a lot of stuff around. That’s why it’s best to do this with a new user. If you want to practice this, I’d say do it to a new user. There’s a link in the preamble to learn how to create a new user.

The command is remarkably simple. Just open up your terminal and run:

sudo usermod -d /path/to/new_home <previous_home>

1	sudo usermod -d /path/to/new_home <previous_home>

So, if I wanted to move my home to /foo/bar, the command would look like:

sudo usermod -d /foo/bar kgiii

1	sudo usermod -d /foo/bar kgiii

You don’t have to specify /home/kgiii – even though that’s the full directory path. The -d command knows that we’re generally talking about the home directory. If you’ve already moved your home directory, and it is outside of the /home directory, you’re probably gonna have to specify that. I don’t actually know, I’ve never tried that.

This isn’t something I’d undertake lightly. I’d really only recommend this on a new user OR if there are some very specific circumstances. You might do this if you’ve filled up your disk space, added a new disk, and want to move your home directory to the new disk so that you don’t have to muck about with changing partitions or anything. Even then, it’s a bad solution – but probably one of the best solutions you have available.

Closure:

Consider this an article that’s for a very special set of circumstances. It’s for when someone on a forum has run out of disk space and wants a way out without any changes to partitioning and doesn’t want to reinstall. This isn’t something you probably need to go playing around with, but you can. I ain’t stopping you. The potential to make a mess of this is pretty strong.

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.

Let’s Make A Symbolic Link

In this article, we’re going to learn how to make a symbolic link. This will be a very easy article, and one you may get some use from. It’s not terribly hard to make a symbolic link, though I suppose the syntax may seem quirky as compared to many other commands. It’s not hard, trust me on this… Or not… You can pretend it’s hard and impress your friends and family!

Ah well…

So, what’s a symbolic link? Well, it’s a link to another file. A symbolic link is a file that contains nothing more than a link to another file. There’s a hard link as well, and that points to an inode. A symbolic link is a bit more versatile. You can make a symbolic link (again, a file) and move it around the system and it’ll still point at the original file. It’s useful if you want to do things like put shortcuts on your desktop.

This being Linux, everything is a file. A symbolic link is a file. It is a file that contains information about where another file is located. Some folks think this sort of stuff is complicated, perhaps too complicated for a new Linux user, but I think it’s easy – so long as it’s properly explained. Darned if I know how to explain it! I hope that worked for you. That’s really all it is. That’s it. It’s just a file that contains information about where another file is located. Everything is a file.

Like I said, this is going to be a short article. It really shouldn’t be all that difficult to show you how to …

Make A Symbolic Link:

Now, pick a file… One that most users will have will be your Bash history, located at ~/.bash_history unless you’ve really done some heavy modifications. Let’s use that file to make a symbolic link.

The format to do this is:

ln -s <existing_file> <new_file>

1	ln -s <existing_file> <new_file>

Obviously, the -s means ‘symbolic’ (feel free to check ‘man ln‘ for more information) and you name the existing file first and then the file you want to create. So, to do this with .bash_history, it’d look like:

ln -s ~/.bash_history ln_test

1	ln -s ~/.bash_history ln_test

Now, you can see it in action:

cat ~/ln_test

1	cat ~/ln_test

Tada! It will show the contents of your .bash_history if you did everything correct. Want to see something even more handy?

mv ~/test ~/Desktop

1	mv ~/test ~/Desktop

Now, look at your desktop and open the file named ‘test’ – or just navigate there in your terminal and check it again with the cat command:

cd ~/Desktop && cat test

1	cd ~/Desktop && cat test

Congratulations! You’ve learned how to make a symbolic link! I told you that it wasn’t all that hard. As a concept, it’s even easier to understand. The syntax to do so isn’t even all that difficult. You’ve got this! I have faith!

Closure:

Yes, yes I did say this would be quick and easy. I think it was. It’s not terribly hard to make a symbolic link and it was a fun article to write. It’s fun to cover some of the basics. As the tagline says, “Getting you up to speed!” Search around or just browse, you might be amazed at the subjects covered!

How To: Reload Your .bash_profile

Today’s article is going to explain how to reload your .bash_profile. It will be just a quick and easy article, one that won’t take up much of your time. It’s not all that complicated, but it’s something folks probably should know.

So, most of you will probably have a .bash_profile. There are other shells, but Bash is the most common. That’s where they store various bash settings. When you make changes to the .bash_profile, the profile needs to be reloaded for the changes to take effect.

I’ve probably covered this elsewhere, though I did write an article to show you how to find out which shell you’re using. If you don’t know, Bash is the name of the shell and stands for Bourne shell. There are many shells, but Bash was the first one ported to Linux. Indeed, it was one of the first applications ported to Linux. It’s still widely used as the default on most distros.

There are times when you’ll want to edit your .bash_profile for additional functionality. It’s where you’d go to change things like terminal output colors and you could even add aliases to the file if you really felt like it. (Those should probably bo in .bash_aliases, for the record.)

With that in mind, I’ll show you how to reload your .bash_profile.

Reload Your .bash_profile:

Like I said, this won’t be a very long article. It’s not terribly complicated.

Let’s say you’ve made a change to your .bash_profile and you want it to take effect immediately. To do that, you enter one of the following two commands:

source .bash_profile

1	source .bash_profile

Alternatively:

source ~/.bash_profile

1	source ~/.bash_profile

You could also close all instances of the terminal and the new .bash_profile changes should take effect the next time you open the terminal. If you really want to have another way, you can reboot and the changes will take effect the next time you open the terminal as that too will reload your .bash_profile.

Closure:

See? I told you this would be a quick and easy article. It’s not all that complicated. You probably don’t need to reload your .bash_profile often, but now you know how to do so when you need to do so. Yup, it’s also another article. There are now more than 250 articles, by the way. Who knew that it’d turn into this?!?

Let’s Learn How To Change The Open File Limit In Linux

Today, lacking anything better to do, we’re going to learn how to change the open file limit in Linux. Why would you want to do this? Buggered if I know! But, I’m gonna tell you how! (You’re welcome!)

Actually, you could be working with many files and want to increase the number of files that can be open at one time. You might also want the opposite, as a way of limiting system resources.

Basically, in Linux, anything that can use resources has some sort of limitation. For example, there’s a limit to how many arguments that can be passed in a single command or for a new process. You’re unlikely to bump into that limit as a regular desktop Linux user, but that limit is there.

Heck, if you want to learn more about that, click this. I’m not entirely sure how to change that value, but it might actually be in some notes somewhere. Someone’s gotta know how.

Again, you’re very unlikely to run into problems as regular ol’ desktop Linux user. Realistically, you’re unlikely to have to change the open file limit in Linux. However, today is the day I tell you how! Why? ‘Cause I ain’t scared – and it’s not my computer that you’re mucking about in!

I should also mention, more to remind you gentlefolk, that everything in Linux is a file. Everything… So, you’d be surprised how many files you have open at times. Even then, you still probably don’t have too much of a need to change the open file limit.

Change The Open File Limit:

Like many articles, this one requires an open terminal. 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 open, now is a good time to tell you that there’s a hard limit and a soft limit. The hard limit can only be changed by root and the soft limit can be altered dynamically by the process.

You can learn those limits. To find the hard limit, use this command:

ulimit -Hn

1	ulimit -Hn

And, to find the soft limit, use this command:

ulimit -Sn

1	ulimit -Sn

Those commands will output the value of your hard and soft limits, respectively.

You can obviously change those limits, else this wouldn’t be an article. To change the open file limit, you just add a new value as an additional argument. It’s something like:

sudo ulimit -Hn <new_value>

1	sudo ulimit -Hn <new_value>

And, again for the soft limit:

sudo ulimit -Sn <new_value>

1	sudo ulimit -Sn <new_value>

For example, you might increase the hard limit with a command like so:

sudo ulimit -Hn 10000

1	sudo ulimit -Hn 10000

If you want to make them permanent changes, you can do that. It’s a little different for the hard limit and the soft limit. So, to make them permanent we need to use nano to do some file editing:

sudo nano /etc/security/limits.conf

1	sudo nano /etc/security/limits.conf

And add this line:

hard nofile <new_limit>

1	hard nofile <new_limit>

If you want to change the soft limit, it’s a little different. It’s just:

<username> soft nofile <new_limit>

1	<username> soft nofile <new_limit>

If it’s not obvious, replace the username with your username (and no brackets, of course). Then, of course, you’ll need to save the file. To do that, just press CTRL + X, then Y, and then ENTER and that’ll save the file properly.

You shouldn’t need to reboot. The changes should be immediate and you can run the above commands to verify this. If the changes somehow didn’t take effect, reboot and you should be good to go.

Closure:

I’ve never really needed to change the open file limit as a desktop Linux user, but you might have a reason to do so. If that’s the case, it makes sense to have this information handy, and now you do.

It’s yet another article in a long, long list of articles – a list that’s growing steadily! I have yet to miss a single publication date, though I feel compelled to do so – as it’d take the pressure off knowing that I no longer have a “perfect” record.