Can't create file with cordova.file.dataDirectory or cordova.file.cacheDirectory

I'm trying to create and write to a file in cordova.file.dataDirectory
(file:///data/data/<package name>/files/) or cordova.file.cacheDirectory.

But without success on android 4.4.2 .
The code fails on :

or using :
fs.root.getFile("myfile.txt",

{ create: true, exclusive: false }

, function () {}, function () {});

Example of code :

window.resolveLocalFileSystemURL(cordova.file.dataDirectory,
function (directoryEntry) { // success
directoryEntry.getFile('myfile.txt',

{ create: true }

,
function (fileEntry) { //success

fileEntry.createWriter(
function (fileWriter) { // success

fileWriter.onwriteend = function ()

{ console.log("OK"); }

;

fileWriter.onerror = function (e)

{ console.log("Not OK"); }

;

// If data object is not passed in,
// create a new Blob instead.
if (!data) {
data = new Blob([' '],

{ type: 'text/plain' }

);
}

data = JSON.stringify(data);
var blob = new Blob([data],

{ type: 'text/plain' }

);

fileWriter.write(blob);
},
function (e)

{ // error console.log(e); }

);
},
function (e)

{ // error console.log(e); }

);
},
function (e)

{ // error console.log(e); }

);

directoryEntry.getFile doesn't work.

However, it works on Android 6