diff --git a/lib/unistd.in.h b/lib/unistd.in.h
index 89c6fd5..b732d57 100644
--- a/lib/unistd.in.h
+++ b/lib/unistd.in.h
@@ -96,11 +96,11 @@ extern int dup2 (int oldfd, int newfd);
    <http://www.opengroup.org/susv3xsh/fchdir.html>.  */
 extern int fchdir (int /*fd*/);
 
-#  define close rpl_close
+#  define close(f) rpl_close(f)
 extern int close (int);
-#  define dup rpl_dup
+#  define dup(o) rpl_dup(o)
 extern int dup (int);
-#  define dup2 rpl_dup2
+#  define dup2(o, n) rpl_dup2(o, n)
 extern int dup2 (int, int);
 
 # endif