blocks|key|2708894|text|Android为Android6.0+(Marshmallow)增加了新的权限模型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2708895|http://www.captechconsulting.com/blogs/runtime-permissions-best-practices-and-how-to-gracefully-handle-permission-removal|offset|length|2708896|因此，您必须检查Runtime权限：|2708897|什么是运行时权限？|2708898|在Android6.0+Marshmallow中，Google引入了一种新的权限模型，允许用户更好地理解应用程序可能请求特定权限的原因。而不是用户在安装时盲目地接受所有权限，而是提示用户接受在应用程序使用过程中变得必要的权限。|2708899|什么时候实施新模式？|2708900|在选择应用程序中的23版本之前，它不需要完全支持。如果您的目标是version+22或更低版本，您的应用程序将在安装时请求所有权限，就像在Marshmallow以下运行操作系统的任何设备上一样。|2708901|这些信息是从这里获取的：|2708902|请检查如何从此链接实现：|2708903|2708904|entityMap|0|LINK|mutability|MUTABLE|url|1^0|0|0|3D|0|0|0|0|0|0|0|0|0|0|3D|1|0^^$0|@$1|2|3|4|5|6|7|12|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|13|8|@]|9|@$D|14|E|15|1|16]]|A|$]]|$1|F|3|G|5|6|7|17|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|18|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|19|8|@]|9|@]|A|$]]|$1|L|3|M|5|6|7|1A|8|@]|9|@]|A|$]]|$1|N|3|O|5|6|7|1B|8|@]|9|@]|A|$]]|$1|P|3|Q|5|6|7|1C|8|@]|9|@]|A|$]]|$1|R|3|S|5|6|7|1D|8|@]|9|@]|A|$]]|$1|T|3|C|5|6|7|1E|8|@]|9|@$D|1F|E|1G|1|1H]]|A|$]]|$1|U|3|-4|5|6|7|1I|8|@]|9|@]|A|$]]]|V|$W|$5|X|Y|Z|A|$10|C]]|11|$5|X|Y|Z|A|$10|C]]]]

Android added new permission model for Android 6.0 (Marshmallow).

<a href="http://www.captechconsulting.com/blogs/runtime-permissions-best-practices-and-how-to-gracefully-handle-permission-removal" rel="nofollow noreferrer">http://www.captechconsulting.com/blogs/runtime-permissions-best-practices-and-how-to-gracefully-handle-permission-removal</a>

So you have to check Runtime Permission :

What Are Runtime Permissions?

With Android 6.0 Marshmallow, Google introduced a new permission model that allows users to better understand why an application may be requesting specific permissions. Rather than the user blindly accepting all permissions at install time, the user is now prompted to accept permissions as they become necessary during application use.

When to Implement the New Model?

it doesn’t require full support until you choose to target version 23 in your application. 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.

This information is taken from here :

Please check How to implement from this link :

<a href="http://www.captechconsulting.com/blogs/runtime-permissions-best-practices-and-how-to-gracefully-handle-permission-removal" rel="nofollow noreferrer">http://www.captechconsulting.com/blogs/runtime-permissions-best-practices-and-how-to-gracefully-handle-permission-removal</a>

blocks|key|3699659|text|如果您的文件存在但无法读取，请确保以下内容：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3699660|许可。因为您可以像您说的那样读取其他文件，所以可能没有问题。|unordered-list-item|3699661|这是而不是文件夹。请用file.isDirectory()检查一下。|offset|length|style|BOLD|CODE|3699662|检查您的文件路径。例如，它不应该像这样开始：file:/...或/home/storage//th+(当您错误地添加两个破折号时)。|3699663|entityMap^0|0|0|2|6|B|I|0|0|8|M|9|W|H|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|Q|8|@]|9|@]|A|$]]|$1|E|3|F|5|D|7|R|8|@$G|S|H|T|I|J]|$G|U|H|V|I|K]]|9|@]|A|$]]|$1|L|3|M|5|D|7|W|8|@$G|X|H|Y|I|J]|$G|Z|H|10|I|K]|$G|11|H|12|I|K]]|9|@]|A|$]]|$1|N|3|-4|5|6|7|13|8|@]|9|@]|A|$]]]|O|$]]

If your file exists but can not read, please make sure the followings: 
- Permission. Because you can read other files as you said, it may not a problem. 
- It is not folder. check it by <code>file.isDirectory()</code>. 
- Check your file path. For example, it should not start like that: <code>file:/...</code> or <code>/home/storage//th</code> (when you mistakenly append with two dashes).

blocks|key|3288156|text|我想这个问题对我的案子来说是很独特的。这个文件是一个系统文件，我的应用程序没有被授予读取它的权限。在我将我的应用程序签署为系统应用程序后，这一问题得到了纠正。|type|unstyled|depth|inlineStyleRanges|offset|length|style|BOLD|entityRanges|data|3288157|其他可能的解决方案可能是，如果应用程序具有读取此类文件的根权限。|3288158|谢谢大家的建议和回答！|3288159|entityMap^0|1F|7|1P|6|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@$9|M|A|N|B|C]|$9|O|A|P|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Q|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|R|8|@]|D|@]|E|$]]|$1|J|3|-4|5|6|7|S|8|@]|D|@]|E|$]]]|K|$]]

I guess the problem was very much unique to my case. The file was a system file and my app was not given the Permission to read it. It was rectified after I signed my app as a system app.

Probable other solution might be if the app will have root permissions to read such file. 

Thanks everyone for your suggestions and answers!!

I am trying to read a system file using bufferedReader in Android API=23 but it gives the following error: open failed: EACCES (Permission denied).

The file is read only. On the other hand, 'cat' command run in adb shell just works fine.

Also, File.exists() returns true for my file whereas File.canRead() returns false.
Is it something related to the administrative/root access?
Does adb shell give you root access to system? 

P.S.:I have granted Read/Write permissions to the app (as per API 23)

Android: unable to read a file using bufferedReader whereas cat command run in adb shell works fine

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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我试图在Android API=23中使用API=23读取一个系统文件，但是它给出了以下错误：打开失败: EACCES (权限拒绝)。该文件是只读的。另一方面，在亚行shell中运行的“cat”命令工作得很好。另外，File.exists()为我的文件返回真，而File.canRead()则返回false。是否与管理/...

问Android:无法使用bufferedReader读取文件，而在亚行shell中运行的cat命令运行良好。
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问Android:无法使用bufferedReader读取文件，而在亚行shell中运行的cat命令运行良好。EN