Index: lpr.c
===================================================================
--- lpr.c	(revision 2180)
+++ lpr.c	(revision 2181)
@@ -114,7 +114,7 @@
 
 static HID lpr_hid;
 
-static int lpr_usage(char *topic)
+static int lpr_usage(const char *topic)
 {
 	fprintf(stderr, "\nlpr exporter command line arguments:\n\n");
 	hid_usage(base_lpr_options, sizeof(base_lpr_options) / sizeof(base_lpr_options[0]));