问如果满足某一条件，如何停止脚本中的"tail -f“并退出？

EN

#!/bin/bash

# get the path to the job script, print help if not passed
jobscr="$1"
[[ -z "$jobscr" ]] && echo "Usage: submit-and-follow [script to submit]" && exit -2

# submit job via SLURM (the job secluder), and get the
# job ID (4-5-digit number) from it's output, exit if failed
jobmsg=$(sbatch "$jobscr")
ret=$?
echo "$jobmsg"
if [ ! $ret -eq 0 ]; then exit $ret; fi
jobid=$(echo "$jobmsg" | cut -d " " -f 4)

# get the stdout and stderr file the job is using, we will log them in another 
# file while we `tail -f` them (this is neccessary due to a file corruption 
# bug in the supercomputer, just assume it makes sense)
outf="$(scontrol show job $jobid | awk -F= '/StdOut=/{print $2}')"
errf="$(scontrol show job $jobid | awk -F= '/StdErr=/{print $2}')"
logf="${outf}.bkp"

# wait for job to start
echo "### Waiting for job $jobid to start..."
until [ -f "$outf" ]; do sleep 5; done


# ~~~~ HERE COMES THE PART IN QUESTION ~~~~ #

# Once it started, start printing the content of stdout and stderr 
# and copy them into the log file
echo "### Job $jobid started, stdout and stderr:"
tail -f -n 100000 $outf $errf | tee $logf &
tail_pid=$! # catch the pid of the child process

# watch for job end (the job id disappears from the queue; consider this 
# detection working), and kill the tail process
while : ; do
    sleep 5
    if [[ -z "$(squeue | grep $jobid)" ]]; then
        echo "### Job $jobid finished!"
        kill -2 $tail_pid
        break
    fi  
done