vold.fstab file in Android 4.3 - android

I want to get the external and internal storage in my app. I'm using this code
Scanner scanner = new Scanner(new File("/etc/vold.fstab"));
while (scanner.hasNext()) {
String line = scanner.nextLine();
if (line.toLowerCase().contains("dev_mount")) {
if (line.toLowerCase().contains("nonremovable")) {
VoldMounts.put(line.split(" ")[2],true);
}else {
VoldMounts.put(line.split(" ")[2],false);
}
}
}
It's working fine on Android 4.2.2 and below, but on Android 4.3 the file is changed to /fstab.<device> and this file needs root access. How can I read the fstab without the need of root access? I don't want to use /proc/mount.
Thanks.

Here is some official information that confirms that "for Android releases 4.3 and later, the various fstab files used by init, vold and recovery were unified in the /fstab. file". As that file has -rw-r----- root root permissions there is no way to read it from an app on a non-rooted device.

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How to read Android 10 devices files with Flutter App

Am using this code to try to read a particular directory an android devices.. this is the code in a released application. it works fine on all devices except SamSung devices..
fetchFromOriginalDirectory() async{
var result = await PhotoManager.requestPermission();//getting permission to check files
if (result) {
Directory dir = Directory('/storage/emulated/0/');
List<FileSystemEntity> _files;
_files = dir.listSync(recursive: true, followLinks: false).reversed.toList();//getting all files(stickers) in this directory
for(FileSystemEntity entity in _files) {//for each file gotten do this
String path = entity.path;
I first thought the problem was this line "/storage/emulated/0/" but after using multiple plugins to check for the right path. i found out the paths are the same. But for some reason the app cant read the files on samsung files. even after all permissions have been granted
Hey guys i fixed it by doing this
<application
android:requestLegacyExternalStorage="true" //adding this line
>
In the android manifest file.

How to save files in External Storage Public Directory DOCUMENTS on Android 4.1.2

i want to save a file on my Android 4.1.2 smartphone in the documents directory.
This code snippet:
File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOCUMENTS),"test.txt");
throws this exception:
E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.NoSuchFieldError: android.os.Environment.DIRECTORY_DOCUMENTS
While this one is working:
File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS),"test.txt");
But i want to save my file in my documents directory, not in downloads. Ive read DIRECTORY_DOCUMENTS is only available in Android 4.4 and higher. But there is also a documents direcotry on my smartphone. So, is there no solution to save it in documents?
Thx for answers
Pebbles
You are not able to access DIRECTORY_DOCUMENTS becuase it is not there in Android 4.1.2. Which means, though there is a Documents directory in your external storage, it is not pointed to by DIRECTORY_DOCUMENTS (since it is non-existent). To solve this, you have to create the directory if it is not present and get the path to that folder manually.
File docsFolder = new File(Environment.getExternalStorageDirectory() + "/Documents");
boolean isPresent = true;
if (!docsFolder.exists()) {
isPresent = docsFolder.mkdir();
}
if (isPresent) {
File file = new File(docsFolder.getAbsolutePath(),"test.txt");
} else {
// Failure
}
The folder is present in older Versions (from Api 1) of Android but the field DIRECTORY_DOCUMENTS is available first in Version 4.4 (Api 19 - Kitkat).
Solution for me was to use Environment.getExternalStorageDirectory() + "/Documents" instead DIRECTORY_DOCUMENTS for older Android Versions.

Can't locate application data on Android phone

I have spent many hours trying to find/create files for an app I am writing. When I pull the application directory name I get: /data/data/com.example.android.[myapp]/files. I am using File(getFilesDir():
File fileDir = new File(getFilesDir() + File.separator);
Log.i(TAG, "File directory: "+fileDir);
When I try to find this path I find many application folders here: Android/data/com but no /data/data folder under Android. There are many other application folders there but not mine. I see the same results whether I use Android Files app or Windows Explorer over USB. I've also tried to look using Eclipse DDMS tab. I see a data folder with a (+) to the left but when I click, it does not expand.
I have also tried creating the directory and file manually with Windows explorer and my app still can't find neither the Android/data/com.example... nor the Android/data/data/com.example... paths.
Also puzzling to me is when the app creates the path and file and write to it (using MODE_WORLD_WRITEABLE) I get no exceptions thrown but then I am unable to read it back or see it with either of the tools mentioned above. I have set the manifest permissions to WRITE_INTERNAL_STORAGE and WRITE_INTERNAL_STORAGE for the app.
Obviously, I am making a very basic mistake.
I am on Android 4.1.2 (API 16).
Sincerely,
ScratchingMyHead
To get the path of my application directory, Try this code sample
PackageManager m = getPackageManager();
String s = getPackageName();
try {
PackageInfo p = m.getPackageInfo(s, 0);
s = p.applicationInfo.dataDir;
} catch (NameNotFoundException e) {
Log.w("yourtag", "Error Package name not found ", e);
}
When I try to find this path I find many application folders here: Android/data/com but no /data/data folder under Android.
That is because you are looking on external storage, not internal storage where your files are. Use DDMS on an emulator to examine internal storage.
I've also tried to look using Eclipse DDMS tab. I see a data folder with a (+) to the left but when I click, it does not expand.
That would sound like what you will get when testing on hardware, as neither you nor DDMS have access to the contents of /data on production hardware.

File exchange PC <--> Android via USB MTP issues

In my android app, I create a file and write some test text into it:
File externalPath = getExternalFilesDir(null);
File importPath = new File(externalPath, "pd-import");
if(!importPath.exists()) {
Log.d(this.getClass().getSimpleName(), "Create import dir: " + importPath.getAbsolutePath());
importPath.mkdirs();
}
File readme = new File(importPath, "README.txt");
try {
FileWriter fw = new FileWriter(readme);
fw.write("This is a test");
fw.flush();
fw.close();
} catch (IOException e) {
e.printStackTrace();
}
This writes the file, which can be approved with an android file browser like B1 File Manager. It's written to HOME/Android/data/JAVA_PACKAGE_NAME/files/pd-import/README.txt
The logcat shows me:
D/MainActivity﹕ Create import dir: /storage/emulated/0/Android/data/JAVA_PACKAGE_NAME/files/pd-import
When I connect my Nexus, where I tested the code, to my Ubuntu Laptop via USB, I see all the other applications data directories like NEXUS 5/Interner Speicher/Android/data/ALL_THE_OTHER_JAVA_PACKAGE_NAMEs ("Interner Speicher" stands for: internal memory). But the folder is not listed for my app is not listed.
Do I need to set some additional medatdata/information/whatever, to have the folder listed over the MTP connection? Anny suggestions?
Does the directory appear when the device is rebooted ? If yes, I think this bug is the cause : https://code.google.com/p/android/issues/detail?id=38282
All phones using MTP instead of USB Mass storage do not properly show
the list of files when that phone is connected to a computer using a
USB cable. Android apps running on the device also cannot see these
files.
This affects files written using Java APIs, but does not appear to
affect files written using the C API.
The solution is to reboot the device.
It does not seem to be resolved.

Accessing FAT32 and NTFS format USB Pendrive from android tablet

We have a USB port in our android tablet(version 4.0.3).
Pendrive File Systems Format are
NTFS
FAT32
When Pendrive File Systems Format are FAT32 File has been created Successfully. But When File Systems Format are NTFS, I got the Error Message as open failed: EACCESS (Permission denied).
I Need to create a New File from in the USB Pendrive. I have tried my sample code is
Button createFile = (Button) findViewById(R.id.createFile);
createFile.setOnClickListener(new OnClickListener()
{
public void onClick(View v)
{
try
{
File root = new File("/mnt/usbhost1");
Runtime.getRuntime().exec("chmod 777 " + root.getAbsolutePath());
File myFile = new File(root,"createNew.txt");
myFile.createNewFile();
Toast.makeText(getBaseContext(), "Done Creating File", Toast.LENGTH_SHORT).show();
}
catch (Exception e)
{
Toast.makeText(getBaseContext(), e.getMessage(), Toast.LENGTH_SHORT).show();
}
}
});
Here /usbhost1 is a Android tablet USB Path. Where I am mistaken. How to create a New File from in the NTFS File Systems Format.
Thanks in advance.
Regards
Bala
What you need is a way to enable support for NTFS in the kernel on your device. This could be achieved dynamically by building the ntfs-driver as loadable module (.ko file). This would need to be done for the specific version of the kernel that is running on your device.
Next you need a way to automatically load the module each time the systems restarts. this is also "do-able" in Android. You might want to try this app which does precisely that. i.e. load one or more kernel module(s) located anywhere on the Android device.
After this whenever one inserts a external-device(usb-drive) that has ntfs partitions, the kernel will be able to properly recognise and mount it. Hence apps can then access it at its proper location like "/mnt/usbhost1" etc.

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