code: function(filedes) {
          // Right now we write all data directly, except for output devices.
          if (FS.streams[filedes] && FS.streams[filedes].object.output) {
            if (!FS.streams[filedes].isTerminal) { // don't flush terminals, it would cause a \n to also appear
              FS.streams[filedes].object.output(null);
            }
          }
        }
docs: int fflush(FILE *stream); http://pubs.opengroup.org/onlinepubs/000095399/functions/fflush.html