diff --git a/mgvams/mg_task_write.cc b/mgvams/mg_task_write.cc
index b67288c..56b0e67 100644
--- a/mgvams/mg_task_write.cc
+++ b/mgvams/mg_task_write.cc
@@ -162,7 +162,7 @@ public: //overrides
       o______ "a0 += \"" << end() << "\";\n";
     }else{
     }
-    o______ "fprintf(stdout, a0.c_str()";
+    o______ "fprintf(stdout, \"%s\", a0.c_str()";
     for(size_t i=1; i<num_args(); ++i) {
       o << ", plain_value(a" << i << ")";
     }