Create schema independent DTL to add FTS segment

 I ike to create schema independent DTL to add FTS segment  to the end of a message. The problem that I see if do I need to loop each segment  to find the last segment ? Or is there a better way to do this?

ClassMethod Transform(source As %RegisteredObject, target As %RegisteredObject) As %Status
{

     set target=source.%ConstructClone(1)
     set FTSseg= "FTS||End Of File|"

ERROR
    quit sc
}