Kill all background jobs

Question

Is there a more compact form of killing background jobs than:

for i in {1..5}; do kill %$i; done

Also, {1..5} obviously has a hard-coded magic number in it, how can I make it "N" with N being the right number, without doing a:

$(jobs | wc -l)

I actually use \j in PS1 to get the # of managed jobs, is this equivalent?

Answer 1

To just kill all background jobs managed by bash, do

kill $(jobs -p)

Note that since both jobs and kill are built into bash, you shouldn't run into any errors of the Argument list too long type.

Answer 2

Use xargs instead of the $(jobs -p) subcommand, because if jobs -p is empty then the kill command will fail.

jobs -p | xargs kill

Answer 3

I guess depending on what output jobs -p gives, the solution could be slightly different. In my case

$ jobs -p
[1]  - 96029 running    some job
[2]  + 96111 running    some other job

Therefore, doing the following is no good.

$ jobs -p | xargs kill
kill: illegal process id: [1]

On the other hand, running kill $(jobs -p) does work but entails a lot of error messages, since the non-PID strings get passed to kill as well.

Therefore, my solution is to grep the PID first and then use xargs, as follows:

$ jobs -p | grep -o -E '\s\d+\s' | xargs kill

Answer 4

I prefer to check if there's any jobs that exist before killing them - this way the script won't fail if there's nothing running.

It's also shorter to type. Throw this in your .bash_profile:

function killjobs () {
    JOBS="$(jobs -p)";
    if [ -n "${JOBS}" ]; then;
        kill -KILL ${JOBS};
    fi
}

Then run:

killjobs

To kill any jobs running.

Answer 5

I have several backgrounded compound commands I want to terminate gracefully, by sending SIGINT to each process, on macOS. None of the other solutions worked properly for that, so I came up with this:

jobs -p | xargs -n1 pkill -SIGINT -g

jobs -p lists background processes started by the current shell.

xargs -n1 executes pkill once for each job.

pkill -SIGINT -g sends SIGINT (same as ctrl+c) to all processes in the process group.

Answer 6

In bash and zsh I would use something like this (after considering the comment from pizdelect about the process group):

jobs -p | extract_pids | xargs --no-run-if-empty kill -TERM -- || true

where

extract_pids() {
    awk '{
        if (NF == 1) { print -$1 }
        else if (NF > 1) {
            if ($2 == "+" || $2 == "-") { print -$3 }
            else { print -$2 }
        }
    }'
}

As far as I tested jobs -p returns the PIDs in bash, f.i.:

$ jobs -p
41659

but can have these formats in zsh, f.i.:

$ jobs -p
[1]    206 running    sleep 10
[2]  - 208 running    sleep 10
[3]  + 210 running    sleep 10

extract_pids tries to handle these (4) cases.

Note: checking the processes with jobs -p can return PIDs, which are already gone at the time xargs kill is invoked, so we ignore errors with a trailing || true.

Answer 7

@pizdelect point is what brought me here. Jobs spawned using pipes have multiple pids. jobs -p is only going to provide the first.

for j in $(jobs | awk '{gsub("[^0-9]","",$1);printf "%%%s\n", $1}');do kill $j;done

If you want to get them all, you have to use the job ID.

Answer 8

Seems like jobs -p | xargs kill does the job, however it produces some unwanted output piped to kill. Here I am grouping output of jobs -p by having/not having + or - character

function killjobs() {
    JOBS=$(jobs -p)
    echo $JOBS | grep -v "+\|-"| awk '{print $2}' | xargs kill -9
    echo $JOBS | grep "+\|-"| awk '{print $3}' | xargs kill -9
}

And later you can just call killjobs