Can someone explain in detail about the various storage locations in Android,
Really confused with these? And are there any methods to access them programatically whenever needed?
I can't speak for storage paths on all phones. But I can explain you clearly with respect to my phone; Coolpad Note 3 - running on Android 5.1. Because, the storage locations or paths may vary on other mobile phones depending on your vendor/manufacturer and different versions of Android OS.
Generally, /someDirectory or /root/someDirectory or >root>someDirectory are same. Which among them is picked to display; depends on your file manager.
On my phone:
/root/sdcard is storage path to phone's internal memory(16 GB in my case).
Both /storage/emulated/0/ and /storage/sdcard0/ are symlinks to /root/sdcard. It means, these two paths are also storage paths of my phone's internal memory.
/storage/sdcard1/ is storage path of my micro SD card.
On ANY phone:
Before Android 4.2, only one user could user your phone. There was no concept of two or more users creating separate profiles and logging into the same phone.
As a result, there were no such paths like /storage/emulated/someDirectory
The emulated directories came up after the introduction of multiuser API in Android 4.2.
So from then,
/storage/emulated/legacy/ points to External Storage(Android terminology) of the currently working user. It would be a symlink.
/storage/emulated/anyNumber/ points to External Storage(Android terminology) of a specific user.
On my phone: I have two users.
internal memory location for user1 (Ramesh) is: /storage/emulated/0/
internal memory location for user2 (Kishore) is: /storage/emulated/10/
So /storage/emulated/legacy/ would point to /storage/emulated/0/ if user1(Ramesh) logs in & uses the phone. In this case, /storage/emulated/legacy/ would be a symlink to /storage/emulated/0/
And /storage/emulated/legacy/ would point to /storage/emulated/10/ if user2(Kishore) logs in & uses the phone. In this case, /storage/emulated/legacy/ would be a symlink to /storage/emulated/10/
If you want to know more about storage paths, please go through this answer on android.stackexchange.com
I specifically mentioned External Storage(Android terminology) above. Because, the Internal and External Storage terminology according to Google/official Android documentation is quite different to that of normal Android OS user.
