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--- a/src/upmpd.hxx
+++ b/src/upmpd.hxx
@@ -28,6 +28,7 @@
 class MpdStatus;
 
 extern std::string g_configfilename;
+extern std::string g_datadir;
 class ConfSimple;
 extern ConfSimple *g_config;
 extern std::string g_protocolInfo;