Update readme

README.md

@@ -9,3 +9,29 @@ names and labels by using a set of regular expressions.
 
 Please refer to this utility's `main()` function for a list of supported
 command line flags.
+
+- - - -
+
+# Building
+
+To build this code, you'll need a working `go` environment. Once you have a suitable environment, simply run the following commands
+
+    go get
+    go build unbound_exporter.go
+
+If your build is working successfully, you should see the following output.
+
+    ./unbound_exporter -h
+    Usage of ./unbound_exporter:
+      -unbound.ca string
+        Unbound server certificate. (default "/etc/unbound/unbound_server.pem")
+      -unbound.cert string
+        Unbound client certificate. (default "/etc/unbound/unbound_control.pem")
+      -unbound.host string
+        Unbound control socket hostname and port number. (default "localhost:8953")
+      -unbound.key string
+        Unbound client key. (default "/etc/unbound/unbound_control.key")
+      -web.listen-address string
+        Address to listen on for web interface and telemetry. (default ":9167")
+      -web.telemetry-path string
+        Path under which to expose metrics. (default "/metrics")