Android 11 - Unable to copy file, 'NO_SPACE_LEFT_ON_TARGET_PATH' despite having a lot of space using SimpleStorage API

Question

I am making a file backup program, using ACTION_OPEN_DOCUMENT_TREE my user picks a folder, then my intent is to copy all items in that folder to the tablet, I do this by saving the URI of the folder the user selects in variable TheURI, I then iterate between all files in the folder by the following

    DocumentFile documentFile = DocumentFile.fromTreeUri(this, TheURI);
        for (DocumentFile file : documentFile.listFiles()) {
            Log.i("",file.getName());
            if(file.isDirectory()){
                Log.i("","is a Directory");
            }else{
                if(file.canRead()||file.canWrite()){
                    savefile(file.getUri());
                }
                Log.i("","is not a Directory");
            }

            Log.i("file.canRead(): " , String.valueOf(file.canRead()));
            Log.i("file.canWrite(): " , String.valueOf(file.canWrite()));

            Log.i("", String.valueOf(file.getUri()));
        }

My savefile function uses SimpleStorage api to grab the absolute file path as follows:

    DocumentFile Filename = DocumentFileCompat.fromUri(this, sourceuri);
        DocumentFileUtils.copyFileTo(Filename, this, "/sdcard/Left", null, new FileCallback() {
            @Override
            public void onConflict(@NotNull DocumentFile destinationFile, @NotNull FileCallback.FileConflictAction action) {
                // do stuff
            }

            @Override
            public void onCompleted(@NotNull Object result) {
                if (result instanceof DocumentFile) {
                    // do stuff
                } else if (result instanceof MediaFile) {
                    // do stuff
                }
            }

            @Override
            public void onReport(Report report) {
                Log.d("%s", String.valueOf(report.getProgress()));
            }

            @Override
            public void onFailed(ErrorCode errorCode) {
                Log.d("Error: %s", errorCode.toString());
            }
        });

I am copying a 500mb file to a tablet that has 20gb of free storage however I get the error

D/Error: %s: NO_SPACE_LEFT_ON_TARGET_PATH

Answer 1

solution found!

When writing to a directory, "/sdcard/" is not a valid path (Most absolute paths aren't) however, if you point directly to the primary storage, which should always be in 'storage/emulated/0' then there will be space. This is pointed out in the SimpleStorage readme, I just missed it!

Turns out grabbing the absolute path still requires you to specify that you're putting it in emulated, because self is always treat as full