Output from my tooling running on 4.1.2: (Not sure all versions affected yet) ``` net.Socket.prototype.bytesWritten throws an exception: TypeError: Cannot read property 'getBuffer' of undefined tls.TLSSocket.super_.prototype.bytesWritten throws an exception: TypeError: Cannot read property 'getBuffer' of undefined tls.TLSSocket.prototype.bytesWritten throws an exception: TypeError: Cannot read property 'getBuffer' of undefined tty.ReadStream.super_.prototype.bytesWritten throws an exception: TypeError: Cannot read property 'getBuffer' of undefined tty.ReadStream.prototype.bytesWritten throws an exception: TypeError: Cannot read property 'getBuffer' of undefined tty.WriteStream.prototype.bytesWritten throws an exception: TypeError: Cannot read property 'getBuffer' of undefined ``` I'm betting a single fix will fix all of them and that it is shared. ### Repro: JS: ``` js var net = require('net') var tls = require('tls') var tty = require('tty') net.Socket.prototype.bytesWritten tls.TLSSocket.super_.prototype.bytesWritten tls.TLSSocket.prototype.bytesWritten tty.ReadStream.super_.prototype.bytesWritten tty.ReadStream.prototype.bytesWritten tty.WriteStream.prototype.bytesWritten ``` output: ``` net.js:730 state.getBuffer().forEach(function(el) { ^ TypeError: Cannot read property 'getBuffer' of undefined at Socket.bytesWritten (net.js:730:8) at Object.<anonymous> (/Users/wmcdonald/devel/newrelic/api-scraper/bad-bytes-written.js:6:21) at Module._compile (module.js:434:26) at Object.Module._extensions..js (module.js:452:10) at Module.load (module.js:355:32) at Function.Module._load (module.js:310:12) at Function.Module.runMain (module.js:475:10) at startup (node.js:118:18) at node.js:952:3 ```