node.js - How do I continuously stream to a child process with node spawn? -


using linux's rev program example (reverses input stdin), following code using node's spawn rev take 1 line stdin , reverse it.

var fs = require ('fs'); const readline = require ('readline');  const rl = readline.createinterface ({     input: process.stdin,     output: process.stdout });  var spawn = require('child_process').spawn; var rev = spawn ('rev');  rev.stdout.on ('data', function (data) {      console.log ('reversed: ' + data); });  rl.on ('line', (line) => {      rev.stdin.write(line);     rev.stdin.end();  })

so, running , entering abc produces reversed: cba

if remove line rev.stdin.end(); in order enter multiple lines, nothing gets output. how continuous output each line entered interactively such:

abc reversed: cba def reversed: fed ...


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