Linux operating system provides several tools and commands for process management, including terminating them. In this article, we will focus on practical examples of terminating a process in Linux using the command line. We'll cover the kill, pkill, and killall commands, as well as some tips on identifying processes to terminate.

Process Identification

Before you terminate a process, you need to know either its PID (Process ID) or its name. You can obtain the PID using the ps or top command. To display a list of running processes with their PIDs, you can use:

ps -aux

or

top

To search for a specific process, you can use grep, for example:

ps -aux | grep [process name]

Terminating a Process using kill

The kill command sends signals to specific processes, with the default signal being SIGTERM (15), which requests the process to terminate. Usage:

kill [PID]

If a process refuses to terminate using SIGTERM, you can use a stronger signal, SIGKILL (9), which forcibly terminates the process:

kill -9 [PID]

Terminating a Process by Name with pkill

The pkill command allows terminating processes by their name, which is useful if you don't know the PID. Its usage is straightforward:

pkill [process name]

Similar to kill, pkill can send various signals, for example:

pkill -9 [process name]

Terminating All Instances of a Process with killall

The killall command terminates all instances of a process with the given name, which is useful if you want to terminate all processes of a particular application:

killall [process name]

To send a SIGKILL signal, use:

killall -9 [process name]

Properly terminating processes is a crucial part of Linux system management. Choosing the right command and signal depends on the situation and desired behavior of the process. It's important to use strong signals like SIGKILL cautiously as they may cause unexpected side effects, including data loss.