Cygwin/X fatal error

[Fergus Daly]

Not quite sure what recent update has caused this failure.
Up to now (and for a very long time indeed) typing
$ /bin/xinit  /bin/xterm  --  -nolock  -multiwindow
at the mintty prompt has successfully started an xterm process.
Now I get:
"A fatal error has occurred and Cygwin/X will now exit.
Cannot establish any listening sockets."
Over the years the one-liner typed above has had to evolve with changing execs so I'm not surprised, or bothered, at this glitch.
But can anybody please advise the necessary change in syntax that will again enable a successful xterm from mintty?
Thank you!