root@mpro20y-rt-1:~# cat 1.sh
#!/bin/bash

screen -S test_name -dm bash -c "mysql -sN -e 'select sleep(10)'"
i=0
while screen -ls test_name &>/dev/null; do
  echo $i && (( i++ )) && sleep 1
done

root@mpro20y-rt-1:~# ./1.sh
0
1
2
3
4
5
6
7
8
9
10

 [[ -n "$not_install" ]] && (apt -y install "$not_install") > /tmp/apt.log &
    bgapt=$!
    
    (wget -qO /tmp/latest.tar.gz https://wordpress.org/latest.tar.gz
    tar zxvf /tmp/latest.tar.gz -C /tmp) >/tmp/wget.log &
    bgwget=$!
    
    progress=' -\|/' i=1
    while [[ -n "$(ps -p ${bgwget} -p ${bgapt} -o pid=)" ]]; do
        sleep 1
        echo -en "${progress:${i}:1} \\b\\b"
        i=$((i % 4 + 1))
    done

if [ $(jobs | wc -l) -ge  ${_PARAM_PARALLEL_APPS_MAX} ]; then
      job_n=($(jobs -p))
      wait ${job_n[0]}
fi

root@mpro20y-rt-1:~# cat 1.sh
#!/bin/bash

sleep 5 &
while true; do
  echo $(jobs) && sleep 1
done

root@mpro20y-rt-1:~# ./1.sh
[1]+ Running sleep 5 &
[1]+ Running sleep 5 &
[1]+ Running sleep 5 &
[1]+ Running sleep 5 &
[1]+ Running sleep 5 &
[1]+ Done sleep 5
[1]+ Done sleep 5
[1]+ Done sleep 5
[1]+ Done sleep 5
^C

root@mpro20y-rt-1:~# ./1.sh
[1]+ Running ( sleep 5 & ) &
[1]+ Done ( sleep 5 & )
[1]+ Done ( sleep 5 & )
[1]+ Done ( sleep 5 & )
[1]+ Done ( sleep 5 & )
[1]+ Done ( sleep 5 & )
^C