md tmp
cd tmp
md old
md old1
md old2
md old3
md new
echo >old/f1
echo >old1/f1
echo >old2/f1
echo >old3/f1

echo >new/f1
echo >>new/f1

diff -ruN old new >temp.patch

patch -p0 -dold1 < temp.patch
patch -p1 -dold1 < temp.patch

cd old2
patch < ../temp.patch
cd ../old3
patch -p0 < ../temp.patch
patch -p1 < ../temp.patch

cd ..
cat old/f1
cat old1/f1
cat old2/f1
cat old3/f1
cat new/f1
cat temp.patch