How to use the private/co.fs function in private

var timer ;
  
  function fire() {
    unlooped = true;
    if (looped) {
      looped = false;
      loop.unloop();
    }
    
    if (timer) {
      clearTimeout(timer);
      timer = null;
    }
  }
  
  Co.fs.stat(__filename, function(err, stat2) {
    Co.println("stat2");
    fire();
  });
  
  timer = setTimeout(function() {
    Co.println('unloop');
    fire();
  });

  if (!unlooped) {
    looped = true;
    loop.loop(); // wait
  }
  
});

Co.path.exists(filename, function(err, exists) {
        if (err) throw err;
        assert.equal(exists, true);
        Co.fs.readFile(filename, function(err, content) {
          if (err) throw err;
          assert.equal(content, 'teardown '+installingDir); // should be cwd.
          return done();
        });
      });
    });

_readContent: function(callback) {
    this.readCount++;
    
    var repo = this;
    Co.fs.readFile(repo.path, function(err, content) {
      if (err) return callback(err);
      repo.content = content;
      callback(null); // ok!
    });
  },

// ==========================================================================
// Project:   Seed - Flexible Package Manager
// Copyright: ©2009-2010 Apple Inc. All rights reserved.
// License:   Licened under MIT license (see __preamble__.js)
// ==========================================================================
/*global process path sys assert libDir __filename */

var Ct = require('core_test:sync');
var loop = require('private/loop');
var Co = require('private/co');

Co.fs.stat(__filename, function(err, stat) {
  Co.println("stat1");

  var looped = false;
  var unlooped = false;
  var timer ;
  
  function fire() {
    unlooped = true;
    if (looped) {
      looped = false;
      loop.unloop();
    }
    
    if (timer) {
      clearTimeout(timer);
      timer = null;

Co.path.exists(filename, function(err, exists) {
    if (err) return done(err);
    if (exists) return Co.fs.rm(filename, done);
    else done();
  });
});