See
Using
the Internal Storage.
A file created with
Context.MODE_PRIVATE
is born with the nine permissions
rw-rw----
and can be read and written only by this app
and by other apps with the same Linux user ID.
To give another app the same Linux user ID as this app,
see
User
IDs and File Access.
A file created with
Context.MODE_WORLD_READABLE | Context.MODE_WORLD_WRITEABLE
is born with the nine permissions
rw-rw-rw-
and can be read and written by other apps.
The vertical bar is the “bitwise or” operator.
adb shell # pwd / # ls -l minus lowercase l dr-x------ root root 2011-04-20 09:19 config drwxrwx--- system cache 2011-04-20 09:19 cache lrwxrwxrwx root root 2011-04-20 09:19 sdcard -> /mnt/sdcard drwxr-xr-x root root 2011-04-20 09:19 acct drwxrwxr-x root system 2011-04-20 09:19 mnt lrwxrwxrwx root root 2011-04-20 09:19 vendor -> /system/vendor lrwxrwxrwx root root 2011-04-20 09:19 d -> /sys/kernel/debug lrwxrwxrwx root root 2011-04-20 09:19 etc -> /system/etc -rw-r--r-- root root 3764 1969-12-31 19:00 ueventd.rc -rw-r--r-- root root 0 1969-12-31 19:00 ueventd.goldfish.rc drwxr-xr-x root root 2011-02-03 17:51 system drwxr-xr-x root root 1969-12-31 19:00 sys drwxr-x--- root root 1969-12-31 19:00 sbin dr-xr-xr-x root root 1969-12-31 19:00 proc -rwxr-x--- root root 13805 1969-12-31 19:00 init.rc -rwxr-x--- root root 1677 1969-12-31 19:00 init.goldfish.rc -rwxr-x--- root root 94168 1969-12-31 19:00 init -rw-r--r-- root root 118 1969-12-31 19:00 default.prop drwxrwx--x system system 2011-04-20 09:20 data drwx------ root root 2010-01-27 19:59 root drwxr-xr-x root root 2011-04-20 09:20 dev # cd data/data/edu.nyu.scps.file # pwd drwxrwx--x app_34 app_34 2011-04-20 11:41 app_subdir drwxr-xr-x system system 2011-04-20 11:41 lib drwxrwx--x app_34 app_34 2011-04-20 10:44 cache drwxrwx--x app_34 app_34 2011-04-20 11:41 files # ls -l -rw-rw---- app_34 app_34 6 2011-04-20 11:46 filename.txt # cat filename.txt hello # rm filename.txt # ls -l filename.txt filename.txt: No such file or directory # exit