adb backup all packages by shell

backup_package.sh

FILENAME="packages.txt"

adb shell pm list package > ./$FILENAME;
echo "packages list output to ./$FILENAME";

cat ./$FILENAME | sed -e 's/package://g' | while read LINE;do
 APKNAME=`echo ${LINE} | tr -d '\r'`
  
if [ ! -e $APKNAME.ab ]; then

  echo "backup start : ${APKNAME}";
  adb backup -apk $APKNAME -shared -f $APKNAME.ab;
  echo "backup complete :  ${APKNAME} \n";

else

  echo "$APKNAME.ab is already backup. skip this line.";

fi

done