diff --git a/src/modules/systemd/libzbxsystemd.h b/src/modules/systemd/libzbxsystemd.h
index 71f2997..b0bdb8c 100644
--- a/src/modules/systemd/libzbxsystemd.h
+++ b/src/modules/systemd/libzbxsystemd.h
@@ -31,11 +31,8 @@
 
 #define LOG_PREFIX              "[systemd] "
 
-// pid that initialised the module, before forking workers.
-int mainpid;
-
 // timeout set by host agent
-int timeout;
+extern int timeout;
 
 // D-Bus api
 #define DBUS_PROPERTIES_INTERFACE     "org.freedesktop.DBus.Properties"
@@ -79,7 +76,7 @@ int dbus_marshall_property(
 #define SYSTEMD_UNIT_INTERFACE        SYSTEMD_SERVICE_NAME ".Unit"
 #define SYSTEMD_SERVICE_INTERFACE     SYSTEMD_SERVICE_NAME ".Service"
 
-DBusConnection *conn;
+extern DBusConnection *conn;
 
 int systemd_get_unit(char *s, size_t n, const char* unit);
 int systemd_unit_is_service(const char *path);