Document commands for diagnosing macOS restarts

Added commands to investigate unexpected system restarts on macOS.

Author: monodot

_articles/macos.md

@@ -8,3 +8,35 @@ title: macOS
 On my Varmilo keyboard:
 
 - **Win + Alt + Fn + F5** shows the Accessibility Shortcuts menu - useful for enabling Full Keyboard Access when connecting a Bluetooth mouse
+
+## Unexpected restarts
+
+Some useful commands to investigate why your system restarted:
+
+```sh
+# Recent reboot history
+last reboot | head -10
+
+# Last boot time
+who -b
+
+# Power management log — sleep/wake/shutdown events
+pmset -g log | grep -E "(Sleep|Wake|Shutdown|Restart|Panic|reboot)" | tail -20
+
+# Shutdown cause codes and kernel panics
+pmset -g log | grep -E "(Shutdown Cause|shutdown cause|kernel panic)" | tail -10
+
+# System log search for shutdown/restart/panic events (adjust --last as needed)
+log show --last 24h --predicate 'eventMessage contains "shutdown" OR eventMessage contains "restart" OR eventMessage contains "panic"' --style syslog | tail -30
+
+# Recent crash/diagnostic reports (kernel panics, watchdog resets, etc.)
+ls -lt ~/Library/Logs/DiagnosticReports/ | head -10
+ls -lt /Library/Logs/DiagnosticReports/ | head -10
+
+# Software update history
+softwareupdate --history
+
+# Recent software install history (all apps)
+system_profiler SPInstallHistoryDataType | grep -B2 -A3 "Date:"
+```
+