Suppress output of `dirs` when calling `pushd`.

ddos-mitigator/superscript.sh

@@ -123,7 +123,8 @@ trap 'sudo -k; popd; rm -r ${tmpdir}' EXIT
 # Create a temp directory, chdir into it and create the (initially empty)
 # banlist file.
 tmpdir=$(mktemp -d)
-pushd "${tmpdir}"
+# Suppress output of dir stack.
+pushd "${tmpdir}" > /dev/null
 touch "${banlist}"
 
 # Parse the command line options