text: // Copyright 2012 The Go Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style
  // license that can be found in the LICENSE file.
  
  // +build !darwin,!dragonfly,!freebsd,!linux,!netbsd,!openbsd,!solaris,!windows
  
  package ipv4
  
  import "golang.org/x/net/internal/socket"
  
  func setControlMessage(c *socket.Conn, opt *rawOpt, cf ControlFlags, on bool) error {
  	return errOpNoSupport
  }
  