overlayfs

rootfs_overlay/overlayfs.sh

@@ -0,0 +1,14 @@
+#!/bin/sh
+set -ex
+lower="${1:-/}"
+mount="$2"
+if [ -z "$mount" ]; then
+  mount="$lower"
+fi
+upper="${lower}/upper"
+work="${lower}/work"
+mkdir -p "$lower" "$upper" "$work" "$mount"
+touch "${lower}/asdf" "${upper}/qwer"
+mount -t overlay -o lowerdir="$lower",upperdir="$upper",workdir="$work" none "$mount"
+ls "$lower" "$upper"
+umount "$mount"