Battery status API in macOS?

Question

How can I read the status of the battery on my MacBookPro from my own application?

Googling has so far only revealed APIs for device drivers to handle power events - there's nothing about user-land processes accessing this information.

thanks.

Chasteen

Answer 1

You'll want to use IOKit for this, specifically the IOPowerSources functions. You can use IOPSCopyPowerSourcesInfo() to get a blob, and IOPSCopyPowerSourcesList() to then extract a CFArray out of that, listing the power sources. Then use IOPSGetPowerSourceDescription() to pull out a dictionary (see IOPSKeys.h for the contents of the dictionary).

Stauder

Answer 2

If you're looking for a quick way to query it from the command line, you'll find the pmset command helpful. To query the battery status, specifically, use:

$ pmset -g batt

Stud

And this is particularly useful when using your Mac remotely via SSH. It's good to know if you need to sprint over to it to connect to the AC! – Byrle

curious that this got so many upvotes, when it's explicitly an API call I was looking for (per the answer I accept) – Chasteen

Plausibly because the question title/tags doesn't distinguish between scripts/CLI and compiled contexts, so many (like myself) find a trivially wrappable answer more useful than an answer that requires me to drop into a specific compiled lang. – Alchemy

Answer 3

Maybe help extracted text into script app

pmset -g batt | head -n 1 | cut -c19- | rev | cut -c 2- | rev

output

Battery Power
AC Power

Agustinaah

Answer 4

For Objective-C, this works to get the current percentage:

NSPipe *pipe = [NSPipe pipe];
NSFileHandle *file = pipe.fileHandleForReading;
NSTask *task = [[NSTask alloc] init];
task.launchPath = @"/usr/bin/pmset -g batt |  perl -ne ' print \"$1\n\" if /([0-9]+%)/'";
NSPipe *pipe = [NSPipe pipe];
task.standardOutput = pipe;
[task launch];
NSData *data = [pipe availableData];

Muzz

Answer 5

Look at the System Management Controller. I don't have my MBP handy, but I believe you need to look at smc.h

Giana