dup2: duplicates in already renumbered files raise a warning not an error
dup2: duplicates in already renumbered files raise a warning not an error

And add some basic TRACE capabilities for debugging

mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs,mancoast/cado-nfs