code: function processStdin(opts, stylize, callback) {
      var leftover = '';  // Left-over partial line from last chunk.
      var stdin = process.stdin;
      stdin.resume();
      stdin.setEncoding('utf8');
      stdin.on('data', function (chunk) {
          var lines = chunk.split(/\r\n|\n/);
          var length = lines.length;
          if (length === 1) {
              leftover += lines[0];
              return;
          }
  
          if (length > 1) {
              handleLogLine(null, leftover + lines[0], opts, stylize);
          }
          leftover = lines.pop();
          length -= 1;
          for (var i = 1; i < length; i++) {
              handleLogLine(null, lines[i], opts, stylize);
          }
      });
      stdin.on('end', function () {
          if (leftover) {
              handleLogLine(null, leftover, opts, stylize);
              leftover = '';
          }
          callback();
      });
  }
docs: Process all input from stdin.
  
  @params opts {Object} Bunyan options object.
  @param stylize {Function} Output stylize function to use.
  @param callback {Function} `function ()`