Fix exit status on failure.
diff --git a/umount.c b/umount.c
index 5f3e59c..eff0804 100644
--- a/umount.c
+++ b/umount.c
@@ -278,7 +278,7 @@
 		else
 			return EXIT_FAILURE;
 	}
-	if (do_umount(*argv, useMtab) == 0)
+	if (do_umount(*argv, useMtab) == TRUE)
 		return EXIT_SUCCESS;
 	perror("umount");
 	return EXIT_FAILURE;