Messages in this thread | | | Date | Wed, 1 Nov 2006 22:27:20 +0100 | From | Pavel Machek <> | Subject | Re: [PATCH v2] Re: Battery class driver. |
| |
Hi!
> >> The suggestions so far were: > >> 1. Append units string to the content of such attribute: > >> /sys/.../capacity_remaining reads "16495 mW". > >> 2. Add a seprate *_units attribute saying what are units for other > >> attribute: > >> /sys/.../capacity_units gives the units for > >> /sys/.../capacity_{remaining,last_full,design,min,...}. > >> 3. Append the units to the attribute names: > >> capacity_{remaining,last_full,design_min,...}:mV. > > > >No, again, one for power and one for current. Two different files > >depending on the type of battery present. That way there is no need to > >worry about unit issues. > > I'm missing something. How is that different from option 3 above? > BTW, please note that we're talking about a large set of files that > use these units (remaining, last full, design capacity, alarm > thresholds, etc.), and not just a single attribute. > > This particular alternative indeed seems cleanest for the kernel side. > The drawback is that someone in userspace who doesn't care about units > but just wants to show a status report or compute the amount of > remaining fooergy divided by the amount of a fooergy when fully > charged, like your typical battery applet, will need to parse > filenames (or try out a fixed and possibly partial list) to find out > which attribute files contain the numbers.
That's okay, we want userspace to use common library, and doing
echo $[`cat capacity_remaining:*` / `cat capacity_total:*`]
is not exactly rocket science. If greg does not like units suffixes, that's okay, too, I'm sure handy wildcard match will be possible. Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |