diff --git a/conn/conn_default.go b/conn/conn_default.go index 4f6b6d1..22248af 100644 --- a/conn/conn_default.go +++ b/conn/conn_default.go @@ -99,7 +99,9 @@ func extractErrno(err error) error { func createBind(uport uint16) (Bind, uint16, error) { var err error var bind nativeBind + var tries int +again: port := int(uport) bind.ipv4, port, err = listenNet("udp4", port) @@ -108,6 +110,10 @@ func createBind(uport uint16) (Bind, uint16, error) { } bind.ipv6, port, err = listenNet("udp6", port) + if uport == 0 && err != nil && extractErrno(err) == syscall.EADDRINUSE && tries < 100 { + tries++ + goto again + } if err != nil && extractErrno(err) != syscall.EAFNOSUPPORT { bind.ipv4.Close() bind.ipv4 = nil diff --git a/conn/conn_linux.go b/conn/conn_linux.go index f6638dd..716028f 100644 --- a/conn/conn_linux.go +++ b/conn/conn_linux.go @@ -104,7 +104,11 @@ func createBind(port uint16) (Bind, uint16, error) { var err error var bind nativeBind var newPort uint16 + var tries int + originalPort := port +again: + port = originalPort // Attempt ipv6 bind, update port if successful. bind.sock6, newPort, err = create6(port) if err != nil { @@ -118,6 +122,10 @@ func createBind(port uint16) (Bind, uint16, error) { // Attempt ipv4 bind, update port if successful. bind.sock4, newPort, err = create4(port) if err != nil { + if originalPort == 0 && err == syscall.EADDRINUSE && tries < 100 { + tries++ + goto again + } if err != syscall.EAFNOSUPPORT { unix.Close(bind.sock6) return nil, 0, err