diff --git a/doc/docbook.sh b/doc/docbook.sh
index 35686bf..29dbc6d 100755
--- a/doc/docbook.sh
+++ b/doc/docbook.sh
@@ -55,7 +55,7 @@ _usage()
 clean=0
 install=0
 uninstall=0
-while getopts "iuP:" "name"; do
+while getopts "ciuP:" name; do
 	case "$name" in
 		c)
 			clean=1