sys/socket.h: add SO_BINDTOIFINDEX from linux v5.1
SO_BINDTOIFINDEX behaves similar to SO_BINDTODEVICE, but takes a
network interface index as argument, rather than the network
interface name. see
linux commit f5dd3d0c9638a9d9a02b5964c4ad636f06cf7e2c
net: introduce SO_BINDTOIFINDEX sockopt
diff --git a/include/sys/socket.h b/include/sys/socket.h
index cd38a4c..8692efa 100644
--- a/include/sys/socket.h
+++ b/include/sys/socket.h
@@ -237,6 +237,7 @@
#define SO_ZEROCOPY 60
#define SO_TXTIME 61
#define SCM_TXTIME SO_TXTIME
+#define SO_BINDTOIFINDEX 62
#ifndef SOL_SOCKET
#define SOL_SOCKET 1