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?

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    It is unclear for what systems you intend this to work. For instance, on Linux I use pkill from procps package. Commented Oct 11, 2012 at 9:55
  • The question was asked from a general point of view . I knew of only two processes like killall and via the awk/sed. But i wanted to know whether there are other ways of achieving this. If it is differently done in different systems, then i want to know what in which. It's very cumbersome to google, instead i thought of discussing with all of you experienced guys. Commented Oct 11, 2012 at 15:35

12 Answers 12


What's wrong with the good old,

for pid in $(ps -ef | grep "some search" | awk '{print $2}'); do kill -9 $pid; done

There are ways to make that more efficient,

for pid in $(ps -ef | awk '/some search/ {print $2}'); do kill -9 $pid; done

and other variations, but at the basic level, it's always worked for me.

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    Up voted, knew of only the first variation. The second looks more efficient, thank you . Commented Oct 11, 2012 at 15:38
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    @TheDarkKnight The problem with this method is that you often end up killing more than you intended. Writing a reliable “some search” is tricky. Under Linux, use pkill, which handles most of the subtleties. Commented Oct 11, 2012 at 22:55
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    I'm not sure it's that tricky, if you're after a specific binary it can be pretty reliable. I always run it as an echo kill -9 $pid first anyway so I know what I'm getting. I'm not sure AIX has pkill, which is my bread and butter UNIX. And is it really bad enough to be down-voted - odd. Commented Oct 12, 2012 at 7:08
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    Unless absolutely necessary, you should send the process SIGTERM instead of SIGKILL.
    – user26112
    Commented Jun 29, 2013 at 16:25
  • I should add that these 2 methods won't work in all shells, for instance it won't work on csh Commented Feb 25, 2016 at 15:55

Use killall,

killall vi

This will kill all command named 'vi'

You might also add a signal as well, e.g SIGKILL

killall -9 vi

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    That's right, you can also add the signal you want, like killall -9 vi Commented Oct 11, 2012 at 7:19
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    I don't think killall is the naswer to it : Killing by file only works for executables that are kept open during execution, i.e. impure executables can't be killed this way. Typing killall name may not have the desired effect on non-Linux systems, especially when done by a privileged user.What if i am trying to delete a lot of instances of some non-linux process ? killall -w doesn't detect if a process disappears and is replaced by a new process with the same PID between scans. If processes change their name, killall may not be able to match them correctly. Commented Oct 11, 2012 at 7:26
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    Please be aware that this only works on Linux and BSD. On Solaris and some other systems killall does exactly what the name suggests...it kills the init-process.
    – Bobby
    Commented Oct 11, 2012 at 9:20
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    On AIX, it "cancels all processes that you started, except those producing the killall process." Commented Oct 12, 2012 at 9:54

pkill is what I recommend, if it's available (Linux, FreeBSD, NetBSD, OpenBSD, Solaris). You can specify processes by the command name, by the full command line or other criteria. For example, pkill vi kills all programs whose command name contains the substring vi. To kill only processes called vi, use pkill -x vi. To kill only processes called vi with a last argument ending in .conf, use pkill -fx 'vi.*\.conf'.

To see the list of PIDs that pkill would send a signal to, use pgrep, which has exactly the same syntax except that it doesn't accept a signal name or number. To see more information about these processes, run

ps -p "$(pgrep …)"

Under Linux, you need ps -p $(pgrep -d, …) instead (that's a bug: Linux's ps isn't POSIX-compliant).

Another common way to identify processes to kill is the processes that have a certain file open (which can be the process's executable). You can list these with fuser; use fuser -k to send them a signal. For example, fuser -k /usr/bin/find kills all running isntances of find.

If there's a runaway process that keeps forking, you may need to kill the whole process group at once. A process group is identified by the negative of its leader, which is the ancestor process of all the processes in the group. To see the process group that a process belongs to, run ps -o pgid (plus any option to select which process(es) to display). If you determine that you want to kill the process group leader 1234 and all its children, run kill -1234 or kill -HUP -1234 or any other signal.

If you can't find a better way, use ps with proper options to list all processes and filter it with grep or some other text filtering command. Take care not to accidentally match other processes that happen to be running a command with a similar name, or with an argument that contains that name. For example:

kill $(ps -o pid -o comm | awk '$2 == "vi" {print $1}')

Remember that your grep or awk command itself may be listed in the ps output (ps and the filtering command are started in parallel, so whether it will show up or not is dependent on timing). This is particularly important if the command arguments are included in the ps output.

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    Thanks a lot, this is really awesome. What you have given is a kind of a tutorial. Thanks again . Up voted Commented Oct 15, 2012 at 6:20
  • To kill a whole process group, there's also -g for pgrep and pkill. Commented Nov 23, 2023 at 19:35

The easiest way to do is first check you are getting right process IDs with:

pgrep -f [part_of_a_command]

If the result is as expected. Go with:

pkill -f [part_of_a_command]

pkill is very nice here. You can give it lots of parameters to refine the pattern.

  • Not available on all UNIXes, and no mention of a specific UNIX or UNIX-like OS in the question. Commented Oct 12, 2012 at 9:50
  • @EightBitTony pkill is available on Linux, BSD and Solaris - afaik. So it has a bigger spread than killall.
    – Nils
    Commented Oct 12, 2012 at 11:12
  • I agree, but killall is even more problematic because there are multiple tools with the same name, that have dramatically different behaviour it would seem. I don't like the killall answers either. pkill doesn't exist on AIX or HP-UX and despite what some people like to believe, there's still a significant based of non-Linux UNIX out in the world. Commented Oct 12, 2012 at 12:21
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    @EightBitTony that is why your answer is the accepted one. But I would not use it on Solaris (which is Unix, too).
    – Nils
    Commented Oct 12, 2012 at 19:18

I would suggest you to try pkill.

Ex: ps -ef | pkill -f command

To show the list of all the processes to be killed first try to pgrep:

Ex: ps -ef | pgrep -f command

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    What is the purpose of piping the output of ps -ef into pkill or pgrep? These commands do not read from standard input.
    – Kusalananda
    Commented Jan 25, 2017 at 12:43

Interesting no one mentioned this one. pidof outputs space-separated pids of processes matching the passed process name. As such, you can directly use its output with kill without piping. On Arch Linux I use

kill -9 $(pidof <proc name>)

The downside to this solution being that it does not allow for use of regular expressions.


You can kill multiple different processes by using the command below

pkill -9 -f "\.\/.+\s\.|process1|process2|process3\[^"

Note that this will kill the process that matches the above pattern, means process1abc process2def process3ghi will also get killed.

  • This is brilliant. Thank you 🙏 Commented Dec 21, 2022 at 14:42

pgrep "name-of-application" | xargs kill -9

Was simple enough to remember and worked nicely for me.

ps -ef | pgrep -f "search" | xargs kill -9  
$ ps -eaf  | grep "xyz" | grep -v grep | awk 'print $2' | xargs kill

write this and name as killer.sh :) infinity loop and killing process

while :
    echo "Press [CTRL+C] to stop.."
    for pid in $(ps -ef | awk '/your process name/ {print $2}'); do kill -9 $pid; done  
    # credit to above answer 
    sleep 1

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