1 files changed, 19 insertions, 0 deletions
diff --git a/interfaces/bindtodevice_darwin.go b/interfaces/bindtodevice_darwin.go
new file mode 100644
index 0000000..5ddfc0e
--- /dev/null
+++ b/interfaces/bindtodevice_darwin.go
@@ -0,0 +1,19 @@
+// +build darwin
+
+package interfaces
+
+import (
+	"net"
+
+	"golang.org/x/sys/unix"
+)
+
+// BindToInterface emulates linux's SO_BINDTODEVICE option for a socket by using
+// IP_BOUND_IF.
+func BindToInterface(fd int, ifname string) error {
+	iface, err := net.InterfaceByName(ifname)
+	if err != nil {
+		return err
+	}
+	return unix.SetsockoptInt(fd, unix.IPPROTO_IP, unix.IP_BOUND_IF, iface.Index)
+}