diff --git a/examples/COUPLE/plugin/liblammpsplugin.c b/examples/COUPLE/plugin/liblammpsplugin.c
index c8a38c21e4..5b1308a5cc 100644
--- a/examples/COUPLE/plugin/liblammpsplugin.c
+++ b/examples/COUPLE/plugin/liblammpsplugin.c
@@ -81,6 +81,7 @@ liblammpsplugin_t *liblammpsplugin_load(const char *lib)
   ADDSYM(python_finalize);
 
   ADDSYM(error);
+  ADDSYM(expand);
 
   ADDSYM(file);
   ADDSYM(command);
diff --git a/examples/COUPLE/plugin/liblammpsplugin.h b/examples/COUPLE/plugin/liblammpsplugin.h
index b444f75215..b2df98d630 100644
--- a/examples/COUPLE/plugin/liblammpsplugin.h
+++ b/examples/COUPLE/plugin/liblammpsplugin.h
@@ -126,6 +126,7 @@ struct _liblammpsplugin {
   void (*python_finalize)();
 
   void (*error)(void *, int, const char *);
+  char *(*expand)(void *, const char *);
 
   void (*file)(void *, const char *);
   char *(*command)(void *, const char *);