Index: release/generate-release.sh
===================================================================
--- release/generate-release.sh	(revision 224801)
+++ release/generate-release.sh	(working copy)
@@ -20,11 +20,20 @@
 # $FreeBSD$
 #
 
-mkdir -p $2/usr/src
+if [ $# -ne 2 ]; then
+	echo >&2 "usage: $(dirname "$0") svn-branch scratch-dir"
+	exit 1
+fi
+
 set -e # Everything must succeed
+if [ -d $2 ]; then
+	(rm -Rf $2; chflags -R noschg $2; rm -Rf $2)
+fi
 
+mkdir -p $2/usr/src
+
 svn co ${SVNROOT:-svn://svn.freebsd.org/base}/$1 $2/usr/src
-if [ ! -z $CVSUP_HOST ]; then
+if [ -n "$CVSUP_HOST" ]; then
 	cat > $2/docports-supfile << EOF
 	*default host=$CVSUP_HOST
 	*default base=/var/db
@@ -35,7 +44,7 @@
 	ports-all
 	doc-all
 EOF
-elif [ ! -z $CVSROOT ]; then
+elif [ -n "$CVSROOT" ]; then
 	cd $2/usr
 	cvs -R ${CVSARGS} -d ${CVSROOT} co -P -r ${CVS_TAG:-HEAD} ports
 	cvs -R ${CVSARGS} -d ${CVSROOT} co -P -r ${CVS_TAG:-HEAD} doc
@@ -47,7 +56,7 @@
 mount -t devfs devfs $2/dev
 trap "umount $2/dev" EXIT # Clean up devfs mount on exit
 
-if [ ! -z $CVSUP_HOST ]; then 
+if [ -n "$CVSUP_HOST" ]; then 
 	cp /etc/resolv.conf $2/etc/resolv.conf
 
 	# Checkout ports and doc trees