[Stuart Cassoff]'s "Communications Endpoints for [Tcl]" [http://www.fivetones.net/software/] gives, among other functionality, [UDP], [IPv6], ... [["... significant demo of Tcl's extensibility (and Tcl_Channel's as well) ..."]] [[... only internal mucking is through ...]] [[... fully compatible with [socket], [tls], ...]] [[?Fit for folding back into [core]?]]