android11 下载会报 Operation not permitted v1.7.7

Before Issue

1. Please search on the Issues
2. Please search on the wiki
3. Please set FileDownloadLog.NEED_LOG=true and review the Logcat output from main process and :filedownloader process ( pay attention to Warn and Error level logcat)

Issue

1. What problem do you get?
2. Which version of FileDownloader are you using when you produce such problem?
3. How to reproduce such problem?
4. Do you set FileDownloadLog.NEED_LOG=true?
5. Could you please reproduce this problem and provide all main process and :filedownloader process logcat
6. Can you fix it by yourself and request PR, if not, what's problem do you get when you try to fix it

P.S. If you don't know how to get :filedownloader process, it's recommended to using pidcat to just filter all your application logcat, or define process.non-separate=true on filedownloader.properties

请在Issue前认真的跟进上面提到的建议，这样将可以极大的加快你遇到问题的处理。

Start by reproducing the Android 11 download failure with FileDownloader v1.7.7 and enable FileDownloadLog.NEED_LOG. Review Warn and Error Logcat output from the main and :filedownloader processes; filedownloader.properties can set process.non-separate=true, and pidcat can filter the application logs. Done means the Operation not permitted failure is reproduced, its cause is identified, and the download works or the required limitation is documented.