perl -d t/22http.t
  DB<1>b IO::Socket::sockname
  DB<2> c
IO::Socket::sockname(C:/strawberry/perl/lib/IO/Socket.pm:245):
245:        @_ == 1 or croak 'usage: $sock->sockname()';

  DB<2> v
244     sub sockname {
245==>b     @_ == 1 or croak 'usage: $sock->sockname()';
246:        getsockname($_[0]);
247     }

  DB<2> x $_[0]
0  HTTP::Daemon=GLOB(0x187d804)
   -> *Symbol::GEN1
         FileHandle({*Symbol::GEN1}) => fileno(7)

  DB<3> n
IO::Socket::sockname(C:/strawberry/perl/lib/IO/Socket.pm:246):
246:        getsockname($_[0]);

  DB<3> n     <--------never returns