diff --git a/misc/spin.sh b/misc/spin.sh
new file mode 100755
index 0000000..9951a57
--- /dev/null
+++ b/misc/spin.sh
@@ -0,0 +1,14 @@
+#!/bin/bash
+# spin.sh -- show a spinner (for coverage test)
+# Copyright (C) 2014  SheetJS
+
+wpid=$1
+delay=1
+str="|/-\\"
+while [ $(ps -a|awk '$1=='$wpid' {print $1}') ]; do
+  t=${str#?}
+  printf " [%c]" "$str"
+  str=$t${str%"$t"}
+  sleep $delay
+  printf "\b\b\b\b"
+done