Using ls

Here’s the latest in an irregular series of short posts that teach some Linux command line basics that you might not know or may have forgotten.

While I keep saying that you don’t need to use the command line in order to use Linux, knowing a few basic commands can be a useful.

Take, for example, times when you have a folder on your hard drive packed with files. Hands up if you don’t have at least one. Yeah, I thought so. Me, too.

How do you effectively and efficiently view the files in a directory? And how do you pinpoint the files that you want to see? By using the ls command, of course.

Let’s take a look at some of the ways in which you can use ls.

Letting Your Fingers Do the Walking

Crack open a terminal and navigate to a folder. Then, type the command ls.

That gives you a listing of all the files in the directory. You get the names of the files but not much else. You can get more information about a file by typing the command ls -l.

Using the -l option, you get the following information:

• The name of the file
• The size of the file in kilobytes
• The permissions on the file
• Who created the file
• Who last modified the file
• The date on which the file was last modified

There’s one more option that I want to look at. It’s -a. When you run ls -a you get a listing of all the files in a directory, including the hidden ones. Hidden files begin with a dot, for example .mozilla.

Using Wildcards

Running ls list all of the files in a folder. Which is OK if there are a few of them. But what not so good if you have a lot of them. You can zero in on a file or type of file by using a wildcard.

For example, let’s say you have a folder filled with songs. And you want to get a listing of all of the Ogg Vorbis files. To do that, run the command **ls *.ogg**.

You can further narrow down the number of files returned by using another wildcard. Like what? Say you want to list all of the MP3 files in a folder whose names contain the word The. To do that, type ls *The*.mp3.

Final Thoughts

The ls command is very useful and very flexible. And it has a number of other options, which you can read about here.

— Scott Nesbitt