Как добавить файлы в папку, пока не будет достигнут определенный предел размера?

Это работает в моем bash:

echo "Folder A"
ls -l ./foldera/
echo "Folder B"
ls -l ./folderb/
echo "Folder C"
ls -l ./folderc/
read -p "Press any key to start"
duplicates=( "$(find foldera folderb -type f -exec basename {} \; |sort |uniq -d)" )
for file in ${duplicates[@]}; do
cp  "./foldera/$file" "./folderc/$file"
done
echo "Script Finish. Folder C"
ls -l ./folderc/

Вывод:

root@debian:# ./bashtest.sh
Folder A
total 32
-rw-r--r-- 1 root root 8230 Oct 14 01:36 abp.png
-rwxr-xr-x 1 root root 8805 Dec  9 01:58 appslist.sh
-rwxrwxrwx 1 root root 2682 Nov 14 02:50 cpu.sh
-rw-r--r-- 1 root root  898 Oct 11 00:25 tkinter-3.py
Folder B
total 24
-rw-r--r-- 1 root root 8230 Oct 14 01:36 abp.png
-rw-r--r-- 1 root root  898 Oct 11 00:25 tkinter-3.py
-rwxr-xr-x 1 root root  595 Oct 28 00:02 yadlist.sh
-rwxr-xr-x 1 root root 2455 Nov 16 01:24 yadnotebook.sh
Folder C
total 0
Press any key to start
Script Finish. Folder C
total 16
-rw-r--r-- 1 root root 8230 Dec 18 23:55 abp.png
-rw-r--r-- 1 root root  898 Dec 18 23:55 tkinter-3.py