diff --git a/chronos/sendfile.nim b/chronos/sendfile.nim
index b93015e3..358643f9 100644
--- a/chronos/sendfile.nim
+++ b/chronos/sendfile.nim
@@ -83,7 +83,7 @@ elif defined(freebsd) or defined(openbsd) or defined(netbsd) or
 elif defined(macosx):
   import posix, os
   type
-    SendfileHeader* {.importc: "sf_hdtr",
+    SendfileHeader* {.importc: "struct sf_hdtr",
                       header: """#include <sys/types.h>
                                  #include <sys/socket.h>
                                  #include <sys/uio.h>""",