Okay, so today I wanted to mess around with processes on my Linux machine, specifically targeting those pesky lingering ones. The big question was: should I use ‘kill’, ‘killall’, or maybe even something else? I decided to call it “kill squint or not,” kinda like a play on words.
Experiment Time!
First, I created a simple background process. I just used the ‘sleep’ command for this, something like:
sleep 1000 &
This puts the ‘sleep’ command in the background, so it won’t tie up my terminal. The ‘&’ is the key here.
Then, I wanted to see its Process ID (PID). So, I typed in:
ps aux grep sleep
This shows me all the processes, and then ‘grep’ filters it down to just the ones with “sleep” in the name. It gave me the PID, which is a unique number for that process.
The ‘kill’ Command
Now, for the killing part! I tried the basic ‘kill’ command first. I typed:
kill [PID]
…replacing ‘[PID]’ with the actual number I got from the ‘ps’ command. And boom, the ‘sleep’ process was gone! ‘kill’ sends a signal to the process, telling it to terminate. By default, it sends a ‘TERM’ signal, which is like a polite request to shut down.
‘killall’ to the Rescue?
Next, I thought, “What if I have multiple ‘sleep’ processes running?” That’s where ‘killall’ comes in. I started a few more ‘sleep’ processes in the background.
sleep 500 &
sleep 700 &
sleep 900 &
Then, instead of finding each PID, I just used:
killall sleep
This killed all processes named “sleep”. Super convenient! ‘killall’ uses the process name instead of the PID.
The Nuclear Option: kill -9
But what if a process is being stubborn and refuses to die? That’s when you bring out the big guns: ‘kill -9’.
I started another ‘sleep’ process. Then I tried:
kill -9 [PID]
Or with killall
killall -9 sleep
The ‘-9’ sends a ‘KILL’ signal (also known as ‘SIGKILL’). This is not polite. It’s a forceful termination. The process doesn’t get a chance to clean up or save anything. It just… dies. It’s generally best to avoid ‘-9’ unless you absolutely have to, because it can lead to data corruption or other problems if the process was in the middle of something important.
My Takeaway
So, “kill squint or not?” Well, it depends.
‘kill [PID]’ is good for single processes when you know the PID.
‘killall [process name]’ is great for killing multiple processes by name.
‘kill -9 [PID]’ or ‘killall -9 [process name]’ is the last resort for unresponsive processes, but use it with caution!
For my simple experiment, regular ‘kill’ or ‘killall’ worked just fine. I only needed ‘-9’ when I deliberately made a process unresponsive. It’s all about choosing the right tool for the job! I hope this little experiment of mine helps someone out there!
