patch/ros-noetic-dynamic-graph.patch

diff --git a/CMakeLists.txt b/CMakeLists.txt
index c1a1f06..8e1a908 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -141,6 +141,10 @@ IF(UNIX)
   TARGET_LINK_LIBRARIES(${PROJECT_NAME} PUBLIC ${CMAKE_DL_LIBS} pthread)
 ENDIF(UNIX)
 
+IF(UNIX AND NOT APPLE)
+  TARGET_LINK_LIBRARIES(${PROJECT_NAME} PUBLIC rt)
+ENDIF(UNIX AND NOT APPLE)
+
 IF(SUFFIX_SO_VERSION)
   SET_TARGET_PROPERTIES(${PROJECT_NAME} PROPERTIES SOVERSION ${PROJECT_VERSION})
 ENDIF(SUFFIX_SO_VERSION)