old_contents: var net = require('net');
  var constant = require('./constants');
  
  var parseExitCode = function(buffer, defaultCode) {
    var tailPos = buffer.length - Buffer.byteLength(constant.EXIT_CODE_0);
  
    if (tailPos < 0) {
      return defaultCode;
    }
  
    // tail buffer which might contain the message
    var tail = buffer.slice(tailPos);
    if (tail.toString() === constant.EXIT_CODE_0) {
      tail.fill('\x00');
      return 0;
    }
  
    return defaultCode;
  };
  
  
  exports.run = function(config) {
    var port = config.runnerPort || constant.DEFAULT_RUNNER_PORT;
    var socket = net.connect(port);
    var exitCode = 1;
  
    // TODO(vojta): error when no Testacular listening on this port
    socket.on('data', function(buffer) {
      exitCode = parseExitCode(buffer, exitCode);
      process.stdout.write(buffer);
    });
  
    socket.on('error', function(e) {
      if (e.code === 'ECONNREFUSED') {
        console.error('There is no server listening on port %d', port);
        process.exit(1);
      } else {
        throw e;
      }
    });
  
    socket.on('end', function() {
      process.exit(exitCode);
    });
  };
  
new_contents: var net = require('net');
  var constant = require('./constants');
  
  var parseExitCode = function(buffer, defaultCode) {
    var tailPos = buffer.length - Buffer.byteLength(constant.EXIT_CODE_0);
  
    if (tailPos < 0) {
      return defaultCode;
    }
  
    // tail buffer which might contain the message
    var tail = buffer.slice(tailPos);
    if (tail.toString() === constant.EXIT_CODE_0) {
      tail.fill('\x00');
      return 0;
    }
  
    return defaultCode;
  };
  
  
  exports.run = function(config) {
    var port = config.runnerPort || constant.DEFAULT_RUNNER_PORT;
    var socket = net.connect(port);
    var exitCode = 1;
  
    // TODO(vojta): error when no Testacular listening on this port
    socket.on('data', function(buffer) {
      exitCode = parseExitCode(buffer, exitCode);
      process.stdout.write(buffer);
    });
  
    socket.on('error', function(e) {
      if (e.code === 'ECONNREFUSED') {
        console.error('There is no server listening on port %d', port);
        process.exit(1);
      } else {
        throw e;
      }
    });
  
    socket.on('close', function() {
      process.exit(exitCode);
    });
  };
  
subject: Fix runner to wait for stdout, stderr