Android Typical Configuration Example Physical primary only (like Nexus One)

Example of external storage configurations as of Android 4.4 for typical devices. Only the relevant portions of the configuration files are included. 

This is a typical configuration for a device with single external storage device which is a physical SD card.
The raw physical device must first be mounted under /mnt/media_rw where only the system and FUSE daemon can access it. vold will then manage the fuse_sdcard0 service when media is inserted/removed.

fstab.hardware

[physical device node]  auto  vfat  defaults  voldmanaged=sdcard0:auto,noemulatedsd

init.hardware.rc

on init
    mkdir /mnt/media_rw/sdcard0 0700 media_rw media_rw
    mkdir /storage/sdcard0 0700 root root

    export EXTERNAL_STORAGE /storage/sdcard0

service fuse_sdcard0 /system/bin/sdcard -u 1023 -g 1023 -d /mnt/media_rw/sdcard0 /storage/sdcard0
    class late_start
    disabled

storage_list.xml

<storage
    android:mountPoint="/storage/sdcard0"
    android:storageDescription="@string/storage_sd_card"
    android:removable="true"
    android:primary="true"
    android:maxFileSize="4096" />

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