SleepTight

A background process for macOS to run programs at sleep and wake up.

The SleepTight project includes:

• A modified version of SleepWatcher 2.2.1 (including C source code, makefile and plist configuration), originally developed by Bernhard Baehr.
• Scripts to eject and reconnect external disks.

SleepWatcher is a command line daemon tool to execute commands when the Mac sleeps or wakes up. See https://www.bernhard-baehr.de/ for more information about the original SleepWatcher.

SleepWatcher 2.2.1 runs on Mac OS X 10.5 and above. This modification, i.e. SleepTight, is tested on macOS Mojave 10.14.4.

The macOS comes with launchd to manage daemon services. The lanuchd is used to run SleepWatcher. Running SleepWatcher as a per-user process (user agent) does not require root permission. SleepTight includes a modified makefile to install SleepWatcher as a user agent. launchd uses a .plist configuration file for each process. For user agent, the .plist file should be stored in ~\Library\LaunchAgents.

For introduction and usage of launchd, see https://www.launchd.info/.

See more details about launchd on Apple Documentation Archive:

• Creating Launch Daemons and Agents
• Technical Notes TN2083: Daemons and agents

Customize the .plist file.

The de.bernhard-baehr.sleepwatcher.plist configures the options for running sleepwatcher. Options are stored as an array under the key ProgramArguments. The default configuration contains the following options:

<array>
    <string>/usr/local/sbin/sleepwatcher</string>
    <string>-V</string>
    <string>-s ~/.sleep</string>
    <string>-w ~/.wakeup</string>
</array>

There are 4 items in the above array:

1. The sleepwatcher binary location.
2. -V, log any action sleepwatcher performs.
3. -s ~/.sleep, execute ~/.sleep file when the system is going into sleep.
4. -w ~/.wakeup, execute ~/.wakeup file when the system is waking up from sleep.

You should either save the files (e.g. shell scripts) you would like to be executed as the ~/.sleep and ~/.wakeup, or change them to the paths of you executable files. The make install command does not create these files. You can also add more options by adding another <string>...</string> to the array.

See the SleepWatcher Manual for all the available options.

By default, the logs are sent to syslog. For debug or logging purpose, you can add the following into the <dict> part so that the standard outputs and errors are saved into the file you specified (/path/to/log/file.log).

<key>StandardErrorPath</key>
<string>/path/to/log/file.log</string>
<key>StandardOutPath</key>
<string>/path/to/log/file.log</string>

Build and Install on macOS Mojave

Use the following commands to create a symlink for libgcc_s:

$ cd /usr/local/lib
$ sudo ln -s ../../lib/libSystem.B.dylib libgcc_s.10.4.dylib

In the source code folder, build the binary for 64-bit system:

$ make sleepwatcher64

Install the binary and manual for the user:

$ make install

The above command will:

• Install the sleepwatcher binary to /usr/local/sbin.
• Install the sleepwatcher manual to /usr/local/share/man/man8.
• Install the de.bernhard-baehr.sleepwatcher.plist to ~/Library/LaunchAgents.

You can also set the path to your customized .plist file by:

$ make install PLIST=path/to/your.plist

Remove the binary from source code folder:

$ make clean

Uninstall

To uninstall SleepWatcher, remove the following 3 files:

• Binary, /usr/local/sbin/sleepwatcher.
• Manual, /usr/local/share/man/man8/sleepwatcher.8.
• Launch Agent, ~/Library/LaunchAgents/de.bernhard-baehr.sleepwatcher.plist.

Known Issue

launchd outputs "This service is defined to be constantly running and is inherently inefficient." when the process starts.

2019 Qiu Qin. SleepTight is part of Qiu's Gemini Project.