I think you have to join Samsung Developers to ask why and how to work around this.
IOW, Google "Samsung Developers."
Me, just another Android author that knows something about this but can't sum up a fix in this small space.
I have an app which will create a folder and save a file in the sdcard which is mounted as portable storage. To do so, I am checking whether my app can write in that path using dir.canWrite api. But android returns false.
Note: I included all the necessary permissions in the Manifest file and also I have included the code for run time permissions.
The same code base works fine with other brand mobile devices. So I want to know whether it is a limitation of samsung.
Thanks in advance

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