Small safety check

server/unixserver.go

@@ -34,6 +34,9 @@ func (s *SocketServer) ServeLine(ctx context.Context, lw unix.LineResponseWriter
 	// on any protocol error.
 	parts := bytes.SplitN(line, []byte{' '}, 2)
 	nargs := len(parts)
+	if nargs < 1 {
+		return errors.New("no command given")
+	}
 	cmd := string(parts[0])
 	switch {
 	case nargs == 1 && cmd == "quit":