add new interface for init configuration (#15)

params_unix.go

@@ -0,0 +1,18 @@
+// +build linux darwin
+
+package water
+
+// PlatformSpecificParams defines parameters in Config that are specific to
+// Linux and macOS. A zero-value of such type is valid, yielding an interface
+// with OS defined name.
+type PlatformSpecificParams struct {
+	// Name is the name to be set for the interface to be created. This overrides
+	// the default name assigned by OS such as tap0 or tun0. A zero-value of this
+	// field, i.e. an emapty string, indicates that the default name should be
+	// used.
+	Name string
+}
+
+func defaultPlatformSpecificParams() PlatformSpecificParams {
+	return PlatformSpecificParams{}
+}