desktop ~ # hddtemp /dev/sda
WARNING: Drive /dev/sda doesn't appear in the database of supported drives
WARNING: But using a common value, it reports something.
WARNING: Note that the temperature shown could be wrong.
WARNING: See --help, --debug and --drivebase options.
WARNING: And don't forget you can add your drive to hddtemp.db
/dev/sda: WDC WD740GD-00FLA1:  31°C or °F
desktop ~ # emerge -pv hddtemp

These are the packages that would be merged, in order:

Calculating dependencies... done!
[ebuild   R   ] app-admin/hddtemp-0.3_beta14-r1  USE="-nls" 0 kB

Total size of downloads: 0 kB