Function isFirstRun

cmd/root/root.go:324–344

isFirstRun checks if this is the first time docker agent is being run. It atomically creates a marker file in the user's config directory using os.O_EXCL to avoid a race condition when multiple processes start concurrently.

()

// using os.O_EXCL to avoid a race condition when multiple processes
// start concurrently.
func isFirstRun() bool {
	configDir := paths.GetConfigDir()
	markerFile := filepath.Join(configDir, ".cagent_first_run")

	// Ensure the config directory exists before trying to create the marker file
	if err := os.MkdirAll(configDir, 0o700); err != nil {
		slog.Warn("Failed to create config directory for first run marker", "error", err)
		return false
	}

	// Atomically create the marker file. If it already exists, OpenFile returns an error.
	f, err := os.OpenFile(markerFile, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0o644) //nolint:gosec // empty marker file with no sensitive content
	if err != nil {
		return false // File already exists or other error, not first run
	}
	if err := f.Close(); err != nil {
		slog.Warn("Failed to close first run marker file", "error", err)
	}

	return true
}