Exception 'open failed: EACCES (Permission denied)' on Android

问题

I am getting

open failed: EACCES (Permission denied)

on the line OutputStream myOutput = new FileOutputStream(outFileName);

I checked the root, and I tried android.permission.WRITE_EXTERNAL_STORAGE.

How can I fix this problem?

try {
    InputStream myInput;

    myInput = getAssets().open(\"XXX.db\");

    // Path to the just created empty db
    String outFileName = \"/data/data/XX/databases/\"
            + \"XXX.db\";

    // Open the empty db as the output stream
    OutputStream myOutput = new FileOutputStream(outFileName);

    // Transfer bytes from the inputfile to the outputfile
    byte[] buffer = new byte[1024];
    int length;
    while ((length = myInput.read(buffer)) > 0) {
        myOutput.write(buffer, 0, length);
    }

    // Close the streams
    myOutput.flush();
    myOutput.close();
    myInput.close();
    buffer = null;
    outFileName = null;
}
catch (IOException e1) {
    // TODO Auto-generated catch block
    e1.printStackTrace();
}

回答1:

I had the same problem... The <uses-permission was in the wrong place. This is right:

 <manifest>
        <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
        ...
        <application>
            ...
            <activity> 
                ...
            </activity>
        </application>
    </manifest>

The uses-permission tag needs to be outside the application tag.

回答2:

For API 23+ you need to request the read/write permissions even if they are already in your manifest.

// Storage Permissions
private static final int REQUEST_EXTERNAL_STORAGE = 1;
private static String[] PERMISSIONS_STORAGE = {
        Manifest.permission.READ_EXTERNAL_STORAGE,
        Manifest.permission.WRITE_EXTERNAL_STORAGE
};

/**
 * Checks if the app has permission to write to device storage
 *
 * If the app does not has permission then the user will be prompted to grant permissions
 *
 * @param activity
 */
public static void verifyStoragePermissions(Activity activity) {
    // Check if we have write permission
    int permission = ActivityCompat.checkSelfPermission(activity, Manifest.permission.WRITE_EXTERNAL_STORAGE);

    if (permission != PackageManager.PERMISSION_GRANTED) {
        // We don't have permission so prompt the user
        ActivityCompat.requestPermissions(
                activity,
                PERMISSIONS_STORAGE,
                REQUEST_EXTERNAL_STORAGE
        );
    }
}

AndroidManifest.xml

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

For official documentation about requesting permissions for API 23+, check https://developer.android.com/training/permissions/requesting.html

回答3:

I have observed this once when running the application inside the emulator. In the emulator settings, you need to specify the size of external storage ("SD Card") properly. By default, the "external storage" field is empty, and that probably means there is no such device and EACCES is thrown even if permissions are granted in the manifest.

回答4:

In addition to all the answers, make sure you're not using your phone as a USB storage.

I was having the same problem on HTC Sensation on USB storage mode enabled. I can still debug/run the app, but I can't save to external storage.

回答5:

My issue was with "TargetApi(23)" which is needed if your minSdkVersion is bellow 23.

So, I have request permission with the following snippet

protected boolean shouldAskPermissions() {
    return (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP_MR1);
}

@TargetApi(23)
protected void askPermissions() {
    String[] permissions = {
            "android.permission.READ_EXTERNAL_STORAGE",
            "android.permission.WRITE_EXTERNAL_STORAGE"
    };
    int requestCode = 200;
    requestPermissions(permissions, requestCode);
}

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
// ...
    if (shouldAskPermissions()) {
        askPermissions();
    }
}

回答6:

Google has a new feature on Android Q: filtered view for external storage. A quick fix for that is to add this code in the AndroidManifest.xml file:

<manifest ... >
    <!-- This attribute is "false" by default on apps targeting Android Q. -->
    <application android:requestLegacyExternalStorage="true" ... >
     ...
    </application>
</manifest>

You can read more about it here: https://developer.android.com/preview/privacy/scoped-storage

回答7:

I'm experiencing the same. What I found is that if you go to Settings -> Application Manager -> Your App -> Permissions -> Enable Storage, it solves the issue.

回答8:

It turned out, it was a stupid mistake since I had my phone still connected to the desktop PC and didn't realize this.

So I had to turn off the USB connection and everything worked fine.

回答9:

I had the same problem on Samsung Galaxy Note 3, running CM 12.1. The issue for me was that i had

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"
    android:maxSdkVersion="18"/>

and had to use it to take and store user photos. When I tried to load those same photos in ImageLoader i got the (Permission denied) error. The solution was to explicitly add

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

since the above permission only limits the write permission up to API version 18, and with it the read permission.

回答10:

In addition to all answers, if the clients are using Android 6.0, Android added new permission model for (Marshmallow).

Trick: If you are targeting version 22 or below, your application will request all permissions at install time just as it would on any device running an OS below Marshmallow. If you are trying on the emulator then from android 6.0 onwards you need to explicitly go the settings->apps-> YOURAPP -> permissions and change the permission if you have given any.

回答11:

I had the same problem and none of suggestions helped. But I found an interesting reason for that, on a physical device, Galaxy Tab.

When USB storage is on, external storage read and write permissions don't have any effect. Just turn off USB storage, and with the correct permissions, you'll have the problem solved.

回答12:

I would expect everything below /data to belong to "internal storage". You should, however, be able to write to /sdcard.

回答13:

Change a permission property in your /system/etc/permission/platform.xml
and group need to mentioned as like below.

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE">
    <group android:gid="sdcard_rw" />
    <group android:gid="media_rw" />    
</uses-permission>

回答14:

I had the same error when was trying to write an image in DCIM/camera folder on Galaxy S5 (android 6.0.1) and I figured out that only this folder is restricted. I simply could write into DCIM/any folder but not in camera. This should be brand based restriction/customization.

回答15:

Strangely after putting a slash "/" before my newFile my problem was solved. I changed this:

File myFile= new File(Environment.getExternalStorageDirectory() + "newFile");

to this:

File myFile= new File(Environment.getExternalStorageDirectory() + "/newFile");

回答16:

Solution for Android Q:

<application ...
    android:requestLegacyExternalStorage="true" ... >

回答17:

When your application belongs to the system application, it can't access the SD card.

回答18:

keep in mind that even if you set all the correct permissions in the manifest: The only place 3rd party apps are allowed to write on your external card are "their own directories" (i.e. /sdcard/Android/data/) trying to write to anywhere else: you will get exception: EACCES (Permission denied)

回答19:

Maybe the answer is this:

on the API >= 23 devices, if you install app (the app is not system app), you should check the storage permission in "Setting - applications", there is permission list for every app, you should check it on! try

回答20:

In my case I was using a file picker library which returned the path to external storage but it started from /root/. And even with the WRITE_EXTERNAL_STORAGE permission granted at runtime I still got error EACCES (Permission denied).
So use Environment.getExternalStorageDirectory() to get the correct path to external storage.

Example:
Cannot write: /root/storage/emulated/0/newfile.txt
Can write: /storage/emulated/0/newfile.txt

boolean externalStorageWritable = isExternalStorageWritable();
File file = new File(filePath);
boolean canWrite = file.canWrite();
boolean isFile = file.isFile();
long usableSpace = file.getUsableSpace();

Log.d(TAG, "externalStorageWritable: " + externalStorageWritable);
Log.d(TAG, "filePath: " + filePath);
Log.d(TAG, "canWrite: " + canWrite);
Log.d(TAG, "isFile: " + isFile);
Log.d(TAG, "usableSpace: " + usableSpace);

/* Checks if external storage is available for read and write */
public boolean isExternalStorageWritable() {
    String state = Environment.getExternalStorageState();
    if (Environment.MEDIA_MOUNTED.equals(state)) {
        return true;
    }
    return false;
}

Output 1:

externalStorageWritable: true
filePath: /root/storage/emulated/0/newfile.txt
isFile: false
usableSpace: 0

Output 2:

externalStorageWritable: true
filePath: /storage/emulated/0/newfile.txt
isFile: true
usableSpace: 1331007488

回答21:

Environment.getExternalStoragePublicDirectory();

When using this deprecated method from Android 29 onwards you will receive the same error:

java.io.FileNotFoundException: open failed: EACCES (Permission denied)

Resolution here:

getExternalStoragePublicDirectory deprecated in Android Q

回答22:

I am creating a folder under /data/ in my init.rc (mucking around with the aosp on Nexus 7) and had exactly this problem.

It turned out that giving the folder rw (666) permission was not sufficient and it had to be rwx (777) then it all worked!

回答23:

The post 6.0 enforcement of storage permissions can be bypassed if you have a rooted device via these adb commands:

root@msm8996:/ # getenforce
getenforce
Enforcing
root@msm8996:/ # setenforce 0
setenforce 0
root@msm8996:/ # getenforce
getenforce
Permissive

回答24:

Add Permission in manifest.

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_INTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

回答25:

after adding permission solved my problem

<uses-permission android:name="android.permission.INTERNET"/>

回答26:

I had the same problem (API >= 23).

The solution https://stackoverflow.com/a/13569364/1729501 worked for me, but it was not practical to disconnect app for debugging.

my solution was to install proper adb device driver on Windows. The google USB driver did not work for my device.

STEP 1: Download adb drivers for your device brand.

STEP 2: Go to device manager -> other devices -> look for entries with word "adb" -> select Update driver -> give location in step 1

回答27:

Add gradle dependencies

implementation 'com.karumi:dexter:4.2.0'

Add below code in your main activity.

import com.karumi.dexter.Dexter;
import com.karumi.dexter.MultiplePermissionsReport;
import com.karumi.dexter.PermissionToken;
import com.karumi.dexter.listener.PermissionRequest;
import com.karumi.dexter.listener.multi.MultiplePermissionsListener;
    @Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_splash);

    new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {


                checkMermission();
            }
        }, 4000);
    }

    private void checkMermission(){
        Dexter.withActivity(this)
                .withPermissions(
                        android.Manifest.permission.READ_EXTERNAL_STORAGE,
                        android.Manifest.permission.WRITE_EXTERNAL_STORAGE,
                        android.Manifest.permission.ACCESS_NETWORK_STATE,
                        Manifest.permission.INTERNET
                ).withListener(new MultiplePermissionsListener() {
            @Override
            public void onPermissionsChecked(MultiplePermissionsReport report) {
                if (report.isAnyPermissionPermanentlyDenied()){
                    checkMermission();
                } else if (report.areAllPermissionsGranted()){
                    // copy some things
                } else {
                    checkMermission();
                }

            }
            @Override
            public void onPermissionRationaleShouldBeShown(List<PermissionRequest> permissions, PermissionToken token) {
                token.continuePermissionRequest();
            }
        }).check();
    }

回答28:

Building on answer by user462990

To be notified when the user responds to the permission request dialog, use this: (code in kotlin)

override fun onRequestPermissionsResult(requestCode: Int,
                           permissions: Array<String>, grantResults: IntArray) {
when (requestCode) {
    MY_PERMISSIONS_REQUEST_READ_CONTACTS -> {
        // If request is cancelled, the result arrays are empty.
        if ((grantResults.isNotEmpty() && grantResults[0] == PackageManager.PERMISSION_GRANTED)) {

            // permission was granted, yay! Do the
            // contacts-related task you need to do.

        } else {

            // permission denied, boo! Disable the
            // functionality that depends on this permission.

        }
        return
    }

    // Add other 'when' lines to check for other
    // permissions this app might request.

    else -> {
        // Ignore all other requests.
    }
}

}

回答29:

In my case the error was appearing on the line

      target.createNewFile();

since I could not create a new file on the sd card,so I had to use the DocumentFile approach.

      documentFile.createFile(mime, target.getName());

For the above question the problem may be solved with this approach,

    fos=context.getContentResolver().openOutputStream(documentFile.getUri());

See this thread too, How to use the new SD card access API presented for Android 5.0 (Lollipop)?

回答30:

For anyone coming here from search results and are targeting Android 10: Android 10 (API 29) changes some permissions related to storage.

I fixed the issue when I replaced my previous instances of Environment.getExternalStorageDirectory() (which is deprecated with API 29) with context.getExternalFilesDir(null).

Note that context.getExternalFilesDir(type) can return null if the storage location isn't available, so be sure to check that whenever you're checking if you have external permissions.

Exception &#39;open failed: EACCES (Permission denied)&#39; on Android

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