Frameserving from FFmpeg to AviSynth

Question

The way my program is set up is that I need to have a stream in FFmpeg, frameserve to an AviSynth script, and then frameserve back to FFmpeg. The entire process is

Java Program->FFmpeg->AviSynth->FFmpeg->Final output file.

The problem I'm having is with jumping from FFmpeg to AviSynth. I saw somewhere that you could open a TCP stream from FFmpeg to AviSynth, but I couldn't get it to work, and that's not that elegant of a solution anyways.

I don't necessarily need to frameserve from just FFmpeg to AviSynth, but I could also just use some way to frameserve from anything to AviSynth. I'd prefer not to use intermediary files. Thanks!