ExternalDisplayAutoBrightnessAgent

Automatically manage brightness of displays connected to your Mac

What It Does

This daemon syncs external monitors with the brightness level of your Mac's built-in display. The goal is to effectively create a single brightness level to worry about, rather than manually keep multiple brightnesses in sync.

Macs without built-in displays are not supported. External monitors must have native macOS support or implement DDC.

By default, the daemon updates every thirty seconds; if you want to change this, modify kTimerRate in main.c. You can tweak kExternalDisplayListMaxSize to lower memory usage.

Install

make install
make install_plist
make run

Manual: Move the executable to /usr/local/libexec, and the plist to ~/Library/LaunchAgents. Run

launchctl load ~/Library/LaunchAgents/net.gofake1.ExternalDisplayAutoBrightnessAgent.plist

to start the daemon.

Build

Requires macOS, a C compiler, and make. Tested on macOS 10.13.

Issues

Report DDC issues to ddcctl. /usr/local/var/log/net.gofake1.ExternalDisplayAutoBrightnessAgent.log contains warnings and errors that would be helpful in bug reports.

Acknowledgments

Authors of brightness.

Authors of ddcctl.

This project is available under the MIT License.