iSMC
is an Apple System Management Controller (SMC) CLI tool that attempts to query SMC for a number of well known keys and determine their type and value, classifying them into temperature, power, current, voltage, fan and battery readouts. It will also attempt to give a human-readable description of each found SMC key.
Apart from regular support for regular (PPC and Intel hardware), it also supports M1 ARM-based SoC hardware which has temperature/voltage/current/power sensors connected to a HID sensor hub.
There are two ways of installing iSMC
(tool works only on macOS computers):
Download your preferred flavor from the releases page and install manually.
CGO_ENABLED=1 go install github.com/dkorunic/iSMC@latest
Usage:
$ iSMC help
Apple SMC CLI tool that can decode and display temperature, fans, battery, power, voltage and current
information for various hardware in your Apple Mac hardware.
Usage:
iSMC [flags]
iSMC [command]
Available Commands:
batt Display battery status
completion Generate the autocompletion script for the specified shell
curr Display current sensors
fans Display fans status
help Help about any command
power Display power sensors
temp Display temperature sensors
volt Display voltage sensors
Flags:
-h, --help help for iSMC
-o, --output string Output format (ascii, table, json) (default "table")
Use "iSMC [command] --help" for more information about a command.
Usage of all commands is self explanatory and all commands have short and long aliases (bat vs. batt vs. battery, cur vs. curr vs. current etc.). There are no flags and/or switches.
I have taken a look at many Apple SMC related projects and took inspiration from them:
- SMCKit Apple SMC library & tool in Swift: github.com/beltex/SMCKit
- SMC API in pure C: github.com/beltex/libsmc
- iStats Ruby Gem for Mac stats: github.com/Chris911/iStats
- smcFanControl tool to control fans in Objective-C (this includes smc-command to query raw SMC keys): github.com/hholtmann/smcFanControl
- FakeSMC Hackintosh kext: github.com/RehabMan/OS-X-FakeSMC-kozlek
- VirtualSMC Hackintosh kext: github.com/acidanthera/VirtualSMC
- osx-cpu-temp to display CPU temperature in pure C: github.com/lavoiesl/osx-cpu-temp
- Linux kernel applesmc.c: github.com/torvalds/linux/blob/master/drivers/hwmon/applesmc.c
- low-level Go bindings for devnull SMC tool: github.com/panotza/gosmc
- Koan-Sin Tan's M1 IOKit demo code: https://github.com/freedomtan/sensors
- Koan-Sin Tan's M1 exploration slides: https://www.slideshare.net/kstan2/exploring-your-apple-m1-devices-with-open-source-tools
- Serhiy Mytrovtsiy's MacOS Stats app: https://github.com/exelban/stats
Planned features:
- fetch and decode SMC key descriptions from SMC,
- generate random SMC keys and fetch/decode if available/usable,
- store those extra (random) SMC keys in permanent configuration file,
- add support for missing types (si*, hex_, pwm, etc.),
- various code cleanups (some parts are downright horrible).
Please open a PR or report an issue. Thanks!