c:\folder1 has many files
a.txt
b.txt
c.txt
output
.folder1.a.txt
.folder2.b.txt
.folder3.c.txt
then c:\folder1\folder2 (in subdir)
abc.txt
cde.txt
cfe.txt
output
.folder1.folder2.abc.txt
.folder1.folder2.cde.txt
.folder1.folder2.cfe.txt
and so on....