Or at least backport patch which add --foreground option to make it possible to run hddtemp daemon under daemontools/runit supervision. Looks like this commit in (probably official, user name is match) repo contains this feature: https://github.com/guzu/hddtemp/commit/e16aed6d0145d7ad8b3308dd0b9199fc701c0417#diff-02f0b547c2779d25cff89672135f20e3R3
*** This bug has been marked as a duplicate of bug 627272 ***