Emscripten processing large stdout as ArrayBuffer

Question

I wonder if there is a way to read large stdout output as ArrayBuffer. So far I have discovered two options:

1. having defined module.print(text => ...) which converts the stdout to text which I need to then reencode into bytes
2. having defined module.stdout(byte => ...) which recieves only a single byte to process

In case of using module.stdout, when looking into module .js, I can see a loop in place:

write:(stream,buffer,offset,length,pos)=>{
    for(var i=0;i<length;i++){
        try{output(buffer[offset+i])} // output() here is reference to my module.stdout
        catch(e){throw new FS.ErrnoError(29)}
    }

which I could change to:

try{output(buffer, offset, length)}

...and so will get what I need inside my module.stdout(). However I would like to avoid doing modifications in this .js file as its being generated by emscripten.

Reading by byte or as a text is suboptimal in my case as it causes unnecessary computation and conversions/loops which slows down the application esp. when dealing with large outputs (GBs).

Do you have any idea how to approach?