Got confused with other people's async walk examples... so created my own.

async_walk.js

var fs = require("fs")

var path = require("path"); //extname, resolve


var pp= console.log
var FILEPATH = "/home/stephan/Music"


// verify with "ls ~/Music/ |wc -l"  in one folder
// "find ~/Music/ -type f | wc -l" recursively!!!
function walk(root_path) {

    var total_results = [];    

    var thread_count = 0;   // OH NOES! I used the word "thread" in node code! Blasphemy!
                            // to be fair though, that's what it eventually becomes.
    (function readdir(target_path) {
        thread_count += 1;
        fs.readdir(target_path,
                   function(err, fsitems) {                   
                       var results = []
                       var total_items = fsitems.length;                   
                       fsitems.forEach(function(item) { 
                           
                           item = path.resolve(target_path, item);
                           
                           if (!fs.statSync(item).isDirectory()) {
                               results.push(item);
                           } else {
                               readdir(item);
                           }
                           
                           if(!--total_items) {
                               total_results = total_results.concat(results);
                               thread_count -= 1;
                           }
                       });
                       
                       if (!thread_count)
                           pp(total_results); // verify with "find ~/Music/ -type f | wc -l"
                   });
    })(root_path);
}

var b = walk(FILEPATH)