mkimage-profiles/features.in/syslinux/scripts.d/20-propagator-ramdisk-syslinux

#!/bin/sh
# postprocess isolinux configuration
# when the image sizes are finally known
# NB: install2_size, live_size, rescue_size get defined here

# validate just in case (see also stage1 Makefile)
if [ -z "$(find $WORKDIR/syslinux/*.cfg)" ]; then
	echo "Warning: syslinux/*.cfg not found"
	exit 0
fi

cd "$WORKDIR"

# apply size census while looking for potential squashfs images
find -maxdepth 1 -type f -size +1M \
| sed 's,^\./,,' \
| while read image; do
	size="$[ $(stat -c%s "$image") / 1024 + 1 ]"
	sed -i "s,@${image}_size@,$size," syslinux/*.cfg
done