why is the system user not allowed to write to the android emulator's sdcard?

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http://stackoverflow.com – I'm writing system apps, but they can't access the emulator's sdcard: root@android:/ # mount | grep 'sdcard vfat' /dev/block/vold/179:0 /mnt/sdcard vfat rw,dirsync,uid=1000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro 0 0 This results in this directory: root@android:/ # ls -ld /mnt/sdcard d---rwxr-x system sdcard_rw 2013-02-05 14:10 sdcard root@android:/ # su system root@android:/ $ ls -l /mnt/sdcard opendir failed, Permission denied My app runs with uid=system, therefore can't access the sdcard. (HowTos)