walk(pathname,callback) for node.js

gistfile1.js

var http = require('http'),
    sys = require('sys'),
    path = require('path'),
    posix = require('posix'),
    events = require('events');

var listdir = function (pathname) {
  var p = new events.Promise();
  var ls = process.createChildProcess("ls", [pathname]);
  ls.addListener("output", function (data) {
    if (data) { 
      var files = [];
      data.split('\n').forEach(function(f) {if (f){files.push(f)}});
      p.emitSuccess(files)
    }
  });
  return p;
}

var walk = function (pathname, callback) {
  listdir(pathname).addCallback(function(files) {
    files.forEach(function(f) {
      var abspath = path.join(pathname, f)
      posix.stat(abspath).addCallback(function(stat) {
        if (stat.isDirectory()) {
          walk(abspath, callback);
        } else {
          callback(abspath);
        }
      }).wait();
    })
  }).wait();
}