overlay save changes example
mkdir MYDIR
overlay save -f
rsync -av --delete --inplace /overlay /tmp/user
[i] /dev/mtdblock7 /tmp/user.MMC jffs2 ro,noatime 0 0
[w] /tmp/user mounted as read only
[i] force mode / remount ro to rw /tmp/user.MMC
sending incremental file list
overlay/root/
overlay/root/MYDIR/
sent 123 bytes received 25 bytes 296.00 bytes/sec
total size is 0 speedup is 0.00
[i] force mode / remount rw to ro /tmp/user.MMC
