[SOLVED] How to wait for a child process to finish in Node.js

I'm running a Python script through a child process in Node.js, like this:

require('child_process').exec('python celulas.py', function (error, stdout, stderr) {
    child.stdout.pipe(process.stdout);
});

but Node doesn't wait for it to finish. How can I wait for the process to finish?

Is it possible to do this by running the child process in a module I call from the main script?

You should use exec-sync

That allow your script to wait that you exec is done

really easy to use:

var execSync = require('exec-sync');

var user = execSync('python celulas.py');