Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [kill]

kill - Send a specified signal to a process or process group.

Questions about the kill shell utility and the kill(2) function on which it is based, which send a signal to a process or a process group.

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What if 'kill -9' does not work?

I have a process I can't kill with kill -9 . What's the problem in such a case, especially since I am the owner of that process. I thought nothing could evade that kill option.
tshepang
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When should I not kill -9 a process?

I am always very hesitant to run kill -9, but I see other admins do it almost routinely. I figure there is probably a sensible middle ground, so: When and why should kill -9 be used? When and why not? What should be tried before doing it? What kind…
Mikel
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How to terminate a background process?

I have started a wget on remote machine in background using &. Suddenly it stops downloading. I want to terminate its process, then re-run the command. How can I terminate it? I haven't closed its shell window. But as you know it doesn't stop using…
Mohammad Etemaddar
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How to kill a runaway cat?

Many times I accidentally run the cat command on files that have contents up to few thousand lines. I try to kill the cat command with Ctrl+ C or Ctrl+Z, but both only take effect after the total output of cat is displayed in the terminal, so I have…
JigarGandhi
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How do I kill all screens?

I accidentally created over 1000 screens. How do I kill them all with one command? (Or a few)
BrainStone
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What does `kill -0` do?

I recently came across this in a shell script. if ! kill -0 $(cat /path/to/file.pid); then ... do something ... fi What does kill -0 ... do?
slm
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Kill all descendant processes

I'm writing an application. It has the ability to spawn various external processes. When the application closes, I want any processes it has spawned to be killed. Sounds easy enough, right? Look up my PID, and recursively walk the process tree,…
MathematicalOrchid
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Kill many instances of a running process with one command

Suppose I have a thousand or more instances of any process (for example, vi) running. How do I kill them all in one single shot/one line command/one command?
The Dark Knight
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How does Linux "kill" a process?

It often baffles me that, although I have been working professionally with computers for several decades and Linux for a decade, I actually treat most of the OS' functionality as a black box, not unlike magic. Today I thought about the kill command,…
seratoninant
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What's the difference between pkill and killall?

I know that pkill has more filtering rules than killall. My question is, what is the difference between: pkill [signal] name and killall [signal] name I've read that killall is more effective and kill all processes and subprocesses (and…
mavillan
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Default exit code when process is terminated?

When a process is killed with a handle-able signal like SIGINT or SIGTERM but it does not handle the signal, what will be the exit code of the process? What about for unhandle-able signals like SIGKILL? From what I can tell, killing a process with…
Cory Klein
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Will Linux start killing my processes without asking me if memory gets short?

I was running a shell script with commands to run several memory-intensive programs (2-5 GB) back-to-back. When I went back to check on the progress of my script I was surprised to discover that some of my processes were Killed, as my terminal…
NeutronStar
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Linux: Kill process based on arguments

How can I kill a process based on its command line arguments? killall, pgrep, and pkill seem to only work based on the process name. I need this to be able to differentiate between a number of applications running inside Java virtual machines,…
Mark Howard
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What is the difference between kill , pkill and killall?

I am familiar with kill command , and most of the time we just use kill -9 to kill a process forcefully, there are many other signals that can be used with kill. But I wonder what are the use cases of pkill and killall, if there is already a kill…
Ijaz Ahmad
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How do I exit or cancel a bad bash command?

I expect to get some flak for this, but I can't find the answer anywhere. It seems like it should be so obvious. Sometimes, when I type a bad command in a bash terminal, the cursor just jumps down to the next line without any error or anything. I…
Big McLargeHuge
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