diff --git a/unshare.c b/unshare.c
index 7251d5e..a8d4aba 100644
--- a/unshare.c
+++ b/unshare.c
@@ -10,7 +10,7 @@
 static void
 usage(void)
 {
-	eprintf("usage: %s [-muinpu] cmd [args...]\n", argv0);
+	eprintf("usage: %s [-muinpU] cmd [args...]\n", argv0);
 }
 
 int