diff --git a/CMakeLists.txt b/CMakeLists.txt
index 9b317e2..6f48124 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -58,6 +58,6 @@ file(GLOB DEMO
 )
 
 add_executable(${lib_name}_demo ${DEMO})
-target_link_libraries(${lib_name}_demo  pthread ${lib_name}_static)
+target_link_libraries(${lib_name}_demo  rt pthread ${lib_name}_static)
 
 include(Package)