In some cases, you may need to kill a process that is not responding. This can be done using the KILL command, which is the most frequent Linux KILL process. The syntax for the KILL command is:

kill -signal pid

Where PID is the process ID of the process you want to terminate. But there are other ways to terminate a Linux process with the command line—and there are some complexities involved, such as knowing the PID.

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What is a process in Linux?

In the Linux operating system, a process is an instance of a running program. Each process has its own unique PID, which is used to identify it. A process can be in one of three states: running, sleeping, or stopped. When you run a program in Linux, a new process is created.

How do you use the Linux KILL process?

The KILL process in the Linux operating system is a very powerful command that can terminate a process with a signal. The command will kill the process immediately. In order to use the KILL process in Linux, you first need to find the PID of the process that you want to terminate. You can do this by running the ps command, which lists processes and their PIDs, or the PIDOF command, which lists the PIDOF of a specific process.

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Once you have the PID of the process you want to terminate, you can use the kill command to signal the process. The most common signal that is used to terminate a process is SIGKILL. However, there are other signals that can be used as well. You can find a list of all the available signals in Linux by running the main kill command. These should work in all major Linux distros.

Why would you kill a process in Linux?

There are many reasons why you might want to kill a process in Linux. One reason might be because the process is not responding, and you need to terminate it to free up resources. Another reason might be that the process takes up too many resources or uses too much of the CPU, and you need to bring it under control. A major advantage to using Linux is that it makes processes more transparent and controllable.

When shouldn’t you kill running processes?

This question might come up in a Linux interview. Killing a process can be dangerous to the stability of your system. If you kill a process that is needed by another process, the system can become unstable. You should only kill processes if you are sure that you need to do so.

How can you avoid killing unnecessary processes?

One way to avoid killing unnecessary processes is to use the TOP command. The TOP command shows all of the processes running on the system and their CPU usage. This can help you identify processes that use too many resources and might need to be terminated.

Another way to avoid killing unnecessary processes is to use the PGREP, and PIDOF commands. The PIDOF command can be used to find the PID of a specific process, while the PGREP command can be used to find all of the processes that match a specific pattern. This can help you to identify and isolate processes that might need to be terminated.

The KILL command can also be used to send a signal to a process other than SIGKILL. This can be useful if you want to terminate a process gracefully or if you want to send a signal that will cause the process to terminate but will also allow it to clean up any resources that it is using.

What processes can’t you kill on a Linux system?

The KILL command can only be used to kill processes running on the local system. If you need to kill a process that is running on another system, you can use the ssh command to connect to the other system and then use the KILL command there.

What are other commands to terminate?

You can use other commands to terminate processes in Linux. The most common of these is the KILLALL command. The KILLALL command can be used to kill all of the processes that match a specific pattern. This can be useful if you want to quickly terminate a group of processes that are causing problems in your system.

You can use another command to terminate processes—the PKILL command. The PKILL command can be used to send a signal to a specific process or group of processes. This can be useful if you want to terminate a not responding process.

Finally, you can use the XKILL command to kill arbitrary processes on the system. You can use the XKILL command to kill processes that are displayed on the screen. This can be useful if you need to terminate a not responding process.

What are the differences between SIGKILL and other signals?

The SIGKILL signal is unique in that it cannot be intercepted or handled by the process. This means that the process will not be able to clean up any resources that it is using before it terminates. Other signals can be intercepted and handled by the process, which gives the process a chance to clean up any resources that it is using. This can prevent the system from becoming unstable if a process is killed unexpectedly.

Do you have the permissions for killing a process?

In order to kill a process, you must have permission to do so. By default, only the root user can kill processes that the root user does not own. If you need to kill a process that another user owns, you must use the SUDO command to gain the permissions required to do so.

The next steps

In the above sections, we discussed how you could use the kill command to terminate processes. We also discussed some of the differences between SIGKILL and other signals. But you will need to know more about the Linux operating system before you may feel comfortable doing things like terminating commands.

Consider learning more about Linux such as which distributions are best, how to use the GREP command in Linux, or the basics of the Linux operating system in a Udemy course.

Page Last Updated: March 2022