Most of Android partitions are mounted as read only.
For eg. /system where most of the libs and other system components are stored, including the permissions.xml file.

You can temporary re-mount the /system partition to read write and load your new files to that partition!

using adb shell or the android terminal with root privileges, do the following:

See the currently mounted partitions:

# mount

Then re-mount to read-write the partition you are interested in , eg. /system:

# mount -o rw,remount -t yaffs2 /dev/block/mtdblock3
# chmod 777 /system

Check the result with mount.

You can also:

mount -o rw,remount -t rootfs /

Now you can write on the Android read-only file system. Sweet!Posted

source from https://www.pocketmagic.net/write-on-the-android-read-only-file-system/

Posted By Radu Motisan on May 14, 2009