iMac Usage for used Machines

[RLRL]

For purchasing a used iMac what is considered low usage?

Using the Terminal Command ac, ac -d,

returns some usage numbers however I am not sure what they really represent.

For Example on my machine, ac returns 2653.25. Is that total days since purchase, total hours?

Using the command ac -d it shows for Mar 23 today, 19.12.

Not sure what that means certainly not hours, and not minutes, because I have been on the machine about 2 hours this morning.

Trying to understand when buying a used Mac how to tell one that does not have much use.

Comments?

 

[wilberforce]

I think ac -d gives connect hours since last boot(s), accumulated over 24 hr periods. Or something like that. (So can be shorter or longer than 24 hrs, depending on when last boot occurred prior to the last 24 hrs).

I think ac -p gives total connect hours since last MacOS update. Not very useful for determining total machine usage.

"man ac"

 

[RLRL]

Thanks