+# This helper script makes it easy to use a passwd or group file to map
+# values in a LOCAL transfer. For instance, if you mount a backup that
+# does not have the same passwd setup as the local machine, you can do
+# a copy TO the backup area as follows and get the differing ID values
+# mapped just like a remote transfer TO the backed-up machine would do:
+#
+# rsync -av --usermap=`mapto /mnt/backup/etc/passwd` \
+# --groupmap=`mapto /mnt/backup/etc/group` \
+# /some/src/ /mnt/backup/some/dest/
+