Not receiving stdout from nodejs spawned process

After going through the Nodejs documentation a few more times, I convinced myself I was either missing something pretty big, or the spawn command wasn't working correctly. So I created a github issue.

And the answer was immediately posted: the child process can't buffer output if you want fast access.

So to achieve what I was originally looking for:

var childProcess = require('child_process');
var spawn = childProcess.spawn;
var child = spawn('unbuffer', 'adventure');

console.log("spawned: " + child.pid);

child.stdout.on('data', function(data) {
  console.log("Child data: " + data);
});
child.on('error', function () {
  console.log("Failed to start child.");
});
child.on('close', function (code) {
  console.log('Child process exited with code ' + code);
});
child.stdout.on('end', function () {
  console.log('Finished collecting data chunks.');
});

With the functional difference being the use of unbuffer, a command that disables output buffering.

Why isn't that initial line from the game being picked up?

I had the same problem on a project that called a compiled C++ program from node.js. I realized the problem was in the compiled C++ program: I wasn't flushing the stdout stream. Adding fflush(stdout); after printing a line solved the issue. Hopefully you still have access to the source of the game!