diff --git a/dtool/src/dtoolutil/load_dso.cxx b/dtool/src/dtoolutil/load_dso.cxx
index 8e59f49de9..0c681d032a 100644
--- a/dtool/src/dtoolutil/load_dso.cxx
+++ b/dtool/src/dtoolutil/load_dso.cxx
@@ -137,6 +137,11 @@ void * load_dso(const DSearchPath &path, const Filename &filename)
   return answer;
 }
 
+bool
+unload_dso(void *dso_handle) {
+  return dlclose(dso_handle)==0;
+}
+
 string
 load_dso_error() {
   char *message = dlerror();