administration

When you type a command into a Linux terminal, what’s really happening is that a program is being executed. Normally, to execute a custom program or script, we need to use its full path, such as /path/to/script.sh or just ./script.sh if we’re already in its residing directory. Alternatively, we can execute a lot of commands without specifying paths, like uptime or date, etc.

The reason we don’t need to specify paths for some commands is because of the $PATH variable. This is a variable that can be configured to tell our Linux system where to look for certain programs. That way, when typing date into the terminal, Linux checks the $PATH variable to see a list of directories to look for the program.

In this guide, we’ll see how to add a directory to the $PATH variable on Linux. This will enable you to call on your program or script from anywhere in the system, without needing to specify the path to where you’ve stored it. Follow along with us as we show how to view the directories in $PATH, and add a directory either temporarily or permanently to the variable.

In this tutorial you will learn:

• How to see currently configured directories in $PATH shell variable
• How to temporarily add directory to $PATH
• How to permanently add directory to $PATH

Adding a directory to $PATH on Linux

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The lsof Linux command is used to list open files. On Linux systems, everything is considered a file. This means that files, directories, sockets, pipes, devices, etc are all files, therefore the lsof command will list all of these things if any of them are in use.

Along with showing you what files are in use, it will give you detailed information about which user and process is using the file. As you can imagine, this can be pretty handy in a multitude of scenarios, such as when trying to figure out what connections are being made to your system or what processes are tying up a disk that you’re trying to unmount, etc.

In this guide, we’ll show you some of the most helpful examples of the lsof command to help you get the most out of it on your own system.

In this tutorial you will learn:

• How to use the lsof command with examples

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Truncating files on a Linux system is a rather basic and common task for users and administrators alike. Perhaps the most common use for truncating (or emptying) a file would be in the case of log files. Clearing a bunch of old data from log files to make way for newer and up to date information can make troubleshooting much easier.

In this tutorial, we’ll show several ways to truncate a file on the Linux command line, including multiple files at once. Use the methods below on your own system, applying the example you feel will best fit your scenario.

In this tutorial you will learn:

• How to use the truncate command
• How to empty a file with Bash shell operator >

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The tar file type is used to combine multiple files into a single archive. Tar actually means “tape archive,” because tar’s original purpose was to be used on tape backups – that should tell you how old this format is. Linux systems still use the tar format, and it continues to enjoy widespread use to this day.

Tar files, with the extension .tar, are often called “tarballs.” These files will preserve the Linux file permissions and can combine any number of files into the single archive, but they don’t apply any compression or space savings. However, compression can be easily applied to the tar file, resulting in extensions like .tar.gz in the case of gzip compression, or .tar.xz for xz compression.

In this guide, we’ll show how to open tar files on command line and via GUI. This will include tar files with various compression applied to the archive. Check out the examples below to find out how.

In this tutorial you will learn:

• How to open tar file via GUI
• How to open tar file via command line

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