diff --git a/genex/genex.c b/genex/genex.c
index 7b8615f..f6160d3 100644
--- a/genex/genex.c
+++ b/genex/genex.c
@@ -21,8 +21,11 @@
 
 static void usage(const char *name)
 {
-	fprintf(stderr, "usage: %s [-L libdir ...] [-l lib ...] hierarchy\n",
-	    name);
+	fprintf(stderr,
+"usage: %s [-L libdir ...] [-l lib ...] hierarchy\n\n"
+"  -L libdir  search all libraries in the specified directory\n"
+"  -l lib     search the specified component library\n"
+    , name);
 	exit(1);
 }