1 files changed, 2 insertions, 1 deletions
diff --git a/bin/tc b/bin/tc
index f73d109..278ca3f 100755
--- a/bin/tc
+++ b/bin/tc
@@ -12,9 +12,10 @@ color() {
 		(5|n|green)  bg='#e0ffe0' ;;
 		(6|o|orange) bg='#fff0f4' ;;
 		(7|k|black)  bg='#111111' fg='#eeeeee' ;;
+		(*) echo "$0: unknown color $1">&2; exit 1 ;;
 	esac
 }
 
 color ${1:-$((RANDOM % 7))}	
-printf '\E]11;'$bg'\E\'
+printf '\E]11;'${bg:-#ffffff}'\E\'
 printf '\E]10;'${fg:-#000000}'\E\'