Broader BSD check

Detailed explanation at https://www.dragonflybsd.org/docs/howtos/howtoporttodragonfly/#index7h3

src/directories.cc

@@ -540,7 +540,7 @@ void Directories::add_or_update_path(const boost::filesystem::path &dir_path, co
   if(path_it==directories.end()) {
     auto g_file=Glib::wrap(g_file_new_for_path(dir_path.string().c_str())); //TODO: report missing constructor in giomm
 
-#if defined(__FreeBSD__)
+#if defined(__OpenBSD__) || defined(__NetBSD__) || defined(__FreeBSD__) || defined(__Darwin__) || defined(__DragonFly__)
     auto monitor=g_file->monitor_directory(Gio::FileMonitorFlags::FILE_MONITOR_SEND_MOVED);
 #else
 #if GLIBMM_MAJOR_VERSION>2 || (GLIBMM_MAJOR_VERSION==2 && GLIBMM_MINOR_VERSION>=44)