Is there a way to make rtorrent write bytes "on-the-go" in the disk?

Question

Hello stackoverflow users,

I am having a bit of trouble getting something to work.

What I want to accomplish?
I want to read bytes (and write them somewhere) while the file is downloading in rtorrent,

First of all, I have rtorrent connected to flood. In my nodejs app I have an interval to get the percentage of files downloaded in rtorrent. Based on the percentage I read "x" bytes from the file it's downloading through rtorrent and writing to user. However, after diving deep into rtorrent writing to disk, I've discovered that rtorrent doesn't write to disk "on-the-go", which means my app won't work.

My question is, is there a way I can make rtorrent write the bytes directly on the disk and not after a certain period ( which I don't know the period, it's just random after many many tests ) ?