hddtemp can be used to determine if an installed drive is sleeping. Typically, it can be used as ...
hddtemp and hdparm can be used together to reset a spin down time and to indicate to the Linux desktop user, that the drive is powered off.

2>&1 hddtemp with RedHat / Fedora does not need a drive. If no drive is specified It uses output of ls /dev/sd?

2>1 hddtemp with SUSE / Tumbleweed requires a drive to be specified, One must specify /dev/sd{a,b,..etc}

Fedora has hddtemp stored in /usr/bin
Suse has hddtemp stored in /usr/sbin

With Fedora I use hddtemp to tell me if the drive is sleeping. I can be a regular user
With SUSE hddtemp is privileged.

I would like to have a consistent definition of execution.

The hddtemp -I does not specify if SUSE or Fedora's way is the correct one. My viewpoint is that we need same functionality.