[OE-core] Setting root password

[Jack Mitchell]

What is the best way to set the root password for an image during build
time?

I have come across this snippet:

ROOTFS_POSTPROCESS_COMMAND += " \
        sed 's%^root:[^:]*:%root:${PASSWD}:%' \
        < ${IMAGE_ROOTFS}/etc/shadow \
        > ${IMAGE_ROOTFS}/etc/shadow.new;\
        mv ${IMAGE_ROOTFS}/etc/shadow.new ${IMAGE_ROOTFS}/etc/shadow ;"

but it feels a bit hacky... is there no defined way to do this cleanly?

Cheers,
Jack.