test.mjs

import fs from 'fs'
const ws=fs.createWriteStream('test.txt',{highWaterMark:50})
let i=1
function write() {
    let canWrite=true
    while (i<=100 && canWrite ) {
        canWrite=ws.write(`line ${i}  \n`)
        console.log('writing',i,'->' ,canWrite)
        ++i
    }
    if (i<=100) {
        ws.once('drain',write)
    }else{
        ws.end()
    }
}
//write()
const fin=fs.createWriteStream('finish.txt')

fin.write('hello\n')
fin.end('finish line \n')
fin.on('close',()=>console.log('closed fired'))
fin.on('finish',()=>console.log('finish fired'))

import EventEmitter from 'events'
const emitter=new EventEmitter()
emitter.emit('split')
emitter.on('split',()=>console.log('split recieved'))
/* 
setInterval(()=>{
    
    
},100) */