1 // Copyright 2012 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4 5 //go:build !aix && !darwin && !dragonfly && !freebsd && !linux && !netbsd && !openbsd && !solaris && !zos
6 7 package ipv4
8 9 import "net"
10 11 // ReadFrom reads a payload of the received IPv4 datagram, from the
12 // endpoint c, copying the payload into b. It returns the number of
13 // bytes copied into b, the control message cm and the source address
14 // src of the received datagram.
15 func (c *payloadHandler) ReadFrom(b []byte) (n int, cm *ControlMessage, src net.Addr, err error) {
16 if !c.ok() {
17 return 0, nil, nil, errInvalidConn
18 }
19 if n, src, err = c.PacketConn.ReadFrom(b); err != nil {
20 return 0, nil, nil, err
21 }
22 return
23 }
24 25 // WriteTo writes a payload of the IPv4 datagram, to the destination
26 // address dst through the endpoint c, copying the payload from b. It
27 // returns the number of bytes written. The control message cm allows
28 // the datagram path and the outgoing interface to be specified.
29 // Currently only Darwin and Linux support this. The cm may be nil if
30 // control of the outgoing datagram is not required.
31 func (c *payloadHandler) WriteTo(b []byte, cm *ControlMessage, dst net.Addr) (n int, err error) {
32 if !c.ok() {
33 return 0, errInvalidConn
34 }
35 if dst == nil {
36 return 0, errMissingAddress
37 }
38 return c.PacketConn.WriteTo(b, dst)
39 }
40