从android image中提取文件

The recovery and boot partitions are at /dev/mtd/mtd1 and /dev/mtd/mtd2, and before you do anything else you should back these up:

# cat /dev/mtd/mtd1 > /sdcard/mtd1.img# cat /dev/mtd/mtd2 > /sdcard/mtd2.img

(Note added by lxrose: These commands don't work if your phone is not rooted and the permissions are not set.)

The other thing you should do is put your favorite update.zip file into the root directory of your sd card so that if you screw up your boot partition you can boot into recovery mode and re-apply the update. You probably want one of the pre-rooted recovery images found elsewhere on the forums.

There is also another important file you should know about. In /system/recovery.img there is a full copy of everything that is loaded on mtd1. This file is automatically flashed onto mtd1 every time you shut down. That means two things: 1. Any changes you make directly to /dev/mtd/mtd1 get blown away on reboot and 2. If you want to change /dev/mtd/mtd1 you're probably better off just sticking the image in /system/recovery.img and rebooting. When creating your own custom update.zip files (especially when adapting the stock images), you can get tripped up if you forget to replace /system/recovery.img and it ends up overwriting /dev/mtd/mtd1 unbeknownst to you. Watch out.

This is not the same thing as applying an update.zip

You will see other places on the forums that describe how to create customized update.zip files, as well as update.zip files that people are sharing. For example, there is a recent update.zip which is a modified version of rc30 (with the anti-root aspects disabled). The update.zip files include new boot images, recovery images, and typically replacements for the entire system/ directory as well as other updates. If you are creating a custom boot or recovery image, it is typically a good idea to start with the image distributed with the most recent update you have applied (flashing an image from an older release could have unintended consequences).

Questions?