Random access through SAF

MainActivity.kt

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        val intent = Intent(Intent.ACTION_OPEN_DOCUMENT)
        intent.type = "*/*"
        intent.addCategory(Intent.CATEGORY_OPENABLE)
        startActivityForResult(intent, 1)
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        if (requestCode == 1 && resultCode == RESULT_OK) {
            if (data != null) {
                val uri = data.data

                val pfd = contentResolver.openFileDescriptor(uri, "r")
                val inputStream = FileInputStream(pfd.fileDescriptor)

                inputStream.skip(995)
                inputStream.skip(-3)
                for (i in 1..10) {
                    val byte = inputStream.read()

                    if (byte == -1) {
                        break;
                    }

                    Log.v("LOL", "${byte.toChar()}");
                }
            }
        }
    }
}