linux

df -h
du -ahx / | sort -rh | head -20

#!/bin/bash

shopt -s nocaseglob nullglob  # Enable case-insensitive matching and skip loop if no match

for file in *.mov; do
  echo "Converting: $file"
  ffmpeg -i "$file" -vn -acodec pcm_s16le "${file%.*}.wav"
done

in linux env

mkdir jail  
sudo cp /bin/bash ./jail/  
tree jail  
ldd /bin/bash # see the dep of bash program  
mkdir /jail/lib64  
sudo cp /lib64/lininfo.so.6 jail/lib64 // etc 5c  
tree jail  
chroot /root/jail/ ./bash // !!!