net: BUG section for ReadFrom, ReadFromIP methods of IPConn on "ip4" network
Fixes #3944.
R=golang-dev, r
CC=golang-dev
https://golang.org/cl/13263043
diff --git a/src/pkg/net/ipraw_test.go b/src/pkg/net/ipraw_test.go
index 1abaf88..5bee21a 100644
--- a/src/pkg/net/ipraw_test.go
+++ b/src/pkg/net/ipraw_test.go
@@ -202,7 +202,7 @@
if _, _, err := c.ReadFrom(rb); err != nil {
t.Fatalf("PacketConn.ReadFrom failed: %v", err)
}
- // TODO: fix issue 3944
+ // See BUG section.
//if net == "ip4" {
// rb = ipv4Payload(rb)
//}
diff --git a/src/pkg/net/iprawsock_posix.go b/src/pkg/net/iprawsock_posix.go
index a73939f..401adda 100644
--- a/src/pkg/net/iprawsock_posix.go
+++ b/src/pkg/net/iprawsock_posix.go
@@ -11,6 +11,18 @@
"time"
)
+// BUG(mikio): On every POSIX platform, reads from the "ip4" network
+// using the ReadFrom or ReadFromIP method might not return a complete
+// IPv4 packet, including its header, even if there is space
+// available. This can occur even in cases where Read or ReadMsgIP
+// could return a complete packet. For this reason, it is recommended
+// that you do not uses these methods if it is important to receive a
+// full packet.
+//
+// The Go 1 compatibliity guidelines make it impossible for us to
+// change the behavior of these methods; use Read or ReadMsgIP
+// instead.
+
func sockaddrToIP(sa syscall.Sockaddr) Addr {
switch sa := sa.(type) {
case *syscall.SockaddrInet4:
