Android File System
SDCard
The mounted SDCard is a storage device mounted to the file system in the typical Linux fashion. On the file system root the /sdcard is a symbolic link to /mnt/sdcard. /mnt/sdcard is where the SD card is actually mounted, but the same files can also be accessed in /sdcard.
- /mnt/sdcard --- Your removable SD card data is stored here.
The Samsung Galaxy Tab 2 actually has two SDCard mounts, one for a built-in internal SDCard which is different than the device memory on a typical Android phone, and the second is the removable SDCard.
- /mnt/extSdCard --- On the Samsung Galaxy 2 tablet this is the removable SD card.
Every Android-compatible device supports a shared "external storage" that you can use to save files. This can be a removable storage media (such as an SD card) or an internal (non-removable) storage. Files saved to the external storage are world-readable and can be modified by the user when they enable USB mass storage to transfer files on a computer.
DCIM
- typically /sdcard/DCIM or /DCIM
Android uses the DCF (Design rule for Camera File system) specification. All digital cameras contain a DCIM (Digital Camera IMages) folder in their root directory. Inside this will be multiple folders named nnnABCDE, where nnn is a unique directory number between 100-999 and ABCDE is a five-character alphanumeric string often (but not required to be) related to the camera manufacturer. Image files stored within these folders will have a file name in the format ABCDnnnn, where ABCD is a four-character string (often DSC_ or IMG_) and nnnn is a unique sequential index number.
External Storage Public Directory
Some people are using a "media" intermediary directory between the standard public directory and the storage root. See below
- /sdcard/media/alarms OR /sdcard/Alarms
- /sdcard/media/notifications OR /sdcard/notifications
- /sdcard/media/ringtones OR /sdcard/ringtones
- /sdcard/media/ui OR /sdcard/ui
Warning: This may be incorrect. Below is from the Android developer's reference explaining the correct way.
Android developer's reference explains that there are certain public storage directories that are not specifically tied to a specific program. So if a program is uninstalled, it should never remove data from one of these standard public storage directories. These directories lay at the root of the external storage, such as Music/, Pictures/, Ringtones/, and others.
- Music/ - Media scanner classifies all media found here as user music.
- Podcasts/ - Media scanner classifies all media found here as a podcast.
- Ringtones/ - Media scanner classifies all media found here as a ringtone.
- Alarms/ - Media scanner classifies all media found here as an alarm sound.
- Notifications/ - Media scanner classifies all media found here as a notification sound.
- Pictures/ - All photos (excluding those taken with the camera).
- Movies/ - All movies (excluding those taken with the camcorder).
- Download/ - Miscellaneous downloads.
So an example would be /mnt/sdcard/Pictures which is made up of the first part, /mnt/sdcard (or just /sdcard) that being the root of the sdcard and then one of the directories above.
Keywords: Android Tablet PC Samsung Galaxy Tab Two 2 FS File System Root Linux