I've seen a number of requests for this functionality and recently it became necessary for one user who had a disabled Home Key to clear cache and data without the use of ClockworkMod. I have reserached two methods to address this issue. These instructions require some familiarity of android, computer and tablet terminology and usage. Feel free to ask for clarifications in comments. Here we go...
Method I - Stock Recovery Command File
Technical: Stock Recovery command file can be used to perform a few additional functions as well as to alter the path to update files. These commands will execute with all privileges available to recovery mode.
Advantages: Very easy to use. Very little technical knowledge required. No third party software is required for use.
Prerequisites: You will need a MicroSD card formatted FAT32 and a method for transferring files from your computer to the MicroSD.
Usage:
1) Prepare a text file named "command" (no file extension) with one of the following commands on a single line. The wipe data command will wipe both data and cache. Wipe cache will wipe cache only.
--wipe_data
--wipe_cache
2) Place the file in a folder named "recovery" in the root directory of your MicroSD card.
3) From a powered down state, insert the MicroSD card into your tablet and boot into recovery by powering it on while holding down the Volume Up key.
4) Allow the command to execute completely then the tablet should reboot (this may not occur automatically depending on firmware installed).
Method II - Updater Script
Technical: The attached "Updater Scripts" perform delete commands (recursively if necessary) on the named directory or file(s). The directories are mounted automatically by the system before the script executes but it could be easily revised to include that step if necessary. The partitioning, formatting and directory structure are left untouched. Only files are deleted.
Advantages: No third party software is necessary for execution. Relatively easy to modify for more surgical precision (i.e. leaving installed apps but clearing possibly corrupted system data). Included example: "Clear Battery Stats"
Prerequisites: You will need a MicroSD card formatted FAT32 and a method for transferring files from your computer to the MicroSD.
Usage:
1) Download the attached archive (ClearData.zip) to your computer.
2) Extract the files to your computer. You should then have a folder named "recovery" (which contains a file named "command") and an additional archive named "update.zip"
3) Place the recovery folder and the update.zip in the root directory of the MicroSD card.
4) From a powered down state, insert the MicroSD card into your tablet and boot into recovery by powering it on while holding down the Volume Up key.
5) Allow the script to execute completely then reboot the tablet (this may occur automatically depending on firmware installed).
This will become handy someday.
Thanks for sharing your knowledge.
You're welcome. One quick note... the new stock recovery adds a menu simiilar to ClockworkMod. These methods will still work since the recovery folder/command file are checked first but it really isn't as necessary any more.
Need Help
Tried both methods above but either way I get to the viewsonic splash with the message "Booting recovery kernel image" in the upper left and it just stays there, stuck there, I left it for a long time to see and it never leaves that screen.
Any ideas?
Me too
I can't get into clockworkmod either. My machine is running faster. I almost hate to mess it more.
lrgche said:
Tried both methods above but either way I get to the viewsonic splash with the message "Booting recovery kernel image" in the upper left and it just stays there, stuck there, I left it for a long time to see and it never leaves that screen.
Any ideas?
Click to expand...
Click to collapse
That's an indication that you may have more serious problems. nvflash will be required. http://forum.xda-developers.com/showthread.php?t=861950
Once done you will likely need to install ClockworkMod and repartition your internal storage.
Loukoebel said:
I can't get into clockworkmod either. My machine is running faster. I almost hate to mess it more.
Click to expand...
Click to collapse
If your tablet boots properly but you can't get into CWM then it probably isn't installed properly (or at all). http://forum.xda-developers.com/showthread.php?t=865245
Keep in mind that CWM is NOT compatible with all ROMs. Make sure the developer for your chosen ROM recommends it before installing it.
Does your method in opening post have to be run from external micro sdcard?
Both methods are performed with an external MicroSD card. They will work from internal also but it is a little more difficult to get the files in place if your tablet is not booting properly.
K J Rad said:
Both methods are performed with an external MicroSD card. They will work from internal also but it is a little more difficult to get the files in place if your tablet is not booting properly.
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Click to collapse
so your method is a simple way to replace one of the main uses of Clockword MOD?--Plus you stay stock more or less.
That is correct. Method II can also be modified to be less intrusive (leave user apps installed) or embedded into update scripts to perform a wipe during new ROM installs.
K J Rad said:
That is correct. Method II can also be modified to be less intrusive (leave user apps installed) or embedded into update scripts to perform a wipe during new ROM installs.
Click to expand...
Click to collapse
Wipe data does what--remove the apps installed?
And the partitions?
Your post is very interesting. It implies that you have a knowledge of the g-tabs partition structure. I have played with Linux off and on for the last 10+ years. When I began, I used Slackware and when you set it up you had to manually create partition tables using fdisk. You were only required to create two - the data partition and a swap partition but it was often recommended that you create several others - one to contain the home directory to prevent users from using all the disk space (in the days of small disks) for example. It appears that there are a lot of partition on the g-tab. Up to now, I have used various wiping tools like clockwork or calkulins wipe all on faith. I would really like to know what all the partitions are and what is in them. I have used terminal to get to the root folder and tried to do an fdisk to display the partitions but try as I might everything remains hidden. It would seem that a script like yours could be adapted to do many things but I would certainly want to understand the structure a little better before I did anything. I have searched and been unable to find that information. Can you point a way for the curious to learn more about the partition structure on the g-tab?
Wish I had a direction I could point you in. What I've found so far has mostly been stumbled upon while looking for something else. What I can tell you is this...
1) When using fdisk in Android you must specify the device to look at. Try something like: fdisk /dev/block/mccblk3 That should list the current partitions as defined by CWM or whatever was used originally.
2) Within one of those partitions in the list generated above are sub-partitions holding the bootloader, system, data, etc partitions. You can see how they're described in the .cfg files in the nvflash restores that are lying about.
lsu205 said:
Wipe data does what--remove the apps installed?
Click to expand...
Click to collapse
Removes user apps and their associated data as well as system related data and settings.
K J Rad - any idea if the partition size can be set with these methods (2048 & 0) in case I can't get clockwork installed?
CodeNamePapa said:
K J Rad - any idea if the partition size can be set with these methods (2048 & 0) in case I can't get clockwork installed?
Click to expand...
Click to collapse
I'm looking for a solution to that problem. Unfortunately these methods still require the ability to get into recovery mode which likely won't work if you're having trouble getting CWM installed.
If, however, you can get into recovery... then it is theoretically possible to create a script that would accomplish that. As soon as I have one I'll be adding it to the mix ;-)
Edit: I've found something I think will work. Will do some testing tonight. It will still require access to recovery.
I wasn't sure if you saw my other post but I am seeing no partition 0 when I NVFlash with a verifypartition.
http://forum.xda-developers.com/showpost.php?p=13059520&postcount=57
I haven't yet but I will. Let's try to keep this thread on topic. Thanks.
More thoughts:
because I went w/ cyan7 is it possible i have a "bad" kernel and that the stock bekit-1105 or the roebeet-3588 files are crashing w/ the kernel in place already?
I know custom ROMs can have a custom kernel applied separately, but I have no idea whether cyan7 loads it's own kernel...
I have yet to try the nvflash_gtablet_46 version, as I see the img files w/in are different from the original 1105 .zip
Also:
read on another thread that part 2 and part 3 aren't loading for other users when doing nvflash - I did notice that it pauses, runs some stuff, then starts loading part 4 through to the last part, then success. - do part 2 and 3 run for you?
edit: I see a 4349 downgrade.zip in another thread for those who got the OTA update but want to go back to stock 3588 prior to jumping off somewhere else - I can't expect that would help me as I can't do squat w/ recovery yet, but could that possibly "reset" any bad kernel problems? - again, I'm just thinking out loud.
This is well outside the scope of this thread but I find some of what you mention interesting so I'll address it and then end any further off topic discussions.
I did not build nor have I ever used Cyan7 so I have no basis for an opinion on the matter other than this... Each ROM comes with a kernel installed so if properly done an nvflash should overwrite any "bad" kernel.
Part2 and Part3 do indeed load, they are just displayed differently than the other Parts. Just minutes ago I flashed down from Mountain Laurel (4349 based with the new bootloader and recovery) with absolutely no trouble. I can, and have, read back those partitions after an nvflash to prove that point.
The 4349 downgrade will only work for you if recovery is working. Having never used it I don't know that it would "reset" the kernel but any subsequent flashing of a new ROM image would.
I am working on a stock recovery solution for partitioning but it isn't likely to help anyone who is stuck in an APX loop. I do have some ideas on what might help for that condition but I haven't been able to get my hands on one for testing and trying to help people here is like being a consulting mechanic for a car repair that's in someone else's shop having work done on it that you're not being told about.
I'll be happy to address any further comments or questions regarding your specific issue in an appropriate thread or via PM. Thanks.
Am I correct, that the data-partition is FAT32 by default? If that is the case, is there a tool available to easily format it to something else (ext,xfs,...) or would I need to do it by hand? How would it be unmounted before, i.e. is it needed to be mounted to have the system running?
I'm asking this, because I'm having trouble moving files (via Airdroid) onto the device, I encounter "Network errors" when filenames contain characters which are illegal on FAT/NTFS. As I'm running pure Linux, ok sometimes OSX, at home and I'm not planning to connect the phone directly to a Windows machine, that would be easier for me.
I think some devs are working on this. For now, I think it isn't possible. Also, Q&A section is for that...
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Ups, sorry, please move.
Ok, thought I could move something like ConnectBot to internal memory and do it from there or the same but via SSH.
I've read a number of forums and such concerning the way this update changes the file system, creating "legacy" and "0" folders and how that may be related to Other category in my Storage settings, which shows over 18 GB used by something I haven't determined.
However, I'm just a simple mechanical engineer and don't really understand what I'm reading regarding this topic. Would it be possible for someone to explain if in more simple terms?
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This has actually been a change in Android itself since 4.2, which included as one of its updates the ability to set up multiple user logins that share the same device. The file structure was rearranged to reflect that change, and the "0" folder represents the main admin user. As for the bloated SD card, I think it's due to some data repetition and needs a full wipe to correct the problem, if I'm not mistaken.
Tremendo Slap said:
This has actually been a change in Android itself since 4.2, which included as one of its updates the ability to set up multiple user logins that share the same device. The file structure was rearranged to reflect that change, and the "0" folder represents the main admin user. As for the bloated SD card, I think it's due to some data repetition and needs a full wipe to correct the problem, if I'm not mistaken.
Click to expand...
Click to collapse
I don't have access to a command prompt on my phone, but I suspect that the legacy and /0 directories are not duplicates. One of the two is what is called a soft link, where the file is listed as in that directory but actually resides somewhere else. When I create a new photo, it shows up in both directory structures.
I am using an unrooted Nexus 5. I am familiar with the public and private data directories in Android.
My question is related to /storage/emulated/legacy. First I see multiple symlinks to this location. Second it is strangely mirrored by /storage/emulated/0.
My real question is this location a hard link with /data/media/0? I cannot see this as I am not rooted. I am asking because I know Android only encrypts /data. I want to make sure the public directories are also encrypted.
This forum moves fast...
Anyway, considering this question can be answered by anyone with root... I assume this one should be answerable.
Hello, I am developing an app for offline navigation, the development goes steady and a more or less usable app is ready now. I am just struggling with one thing, I now put the map files in <SD_CARD>/Pictures/osmscout and add picture_files_read to the apparmor file. Of course Pictures is not the right location for maps, but how can I give my app rights for another location on the sd card, like <SD_CARD>/Maps/osmscout or something?
The description of picture_files_read in the ubuntu-sdk apparmor dialog says that this apparmor profile should give read access to /media/*/r (at least temporarily) however it doesn't actually give me permissions to any other location than Pictures.
Any ideas?
Thanks
Ubuntu prevents file system access to any other location than your own data, cache and config directories by design. That decision was made to improve the security of the system.
However, as noted, you do have write access to three directories:
Code:
~/.local/share/package.name (for user data)
~/.cache/package.name (for caching)
~/.config/package.name (for config files)
The directory which would be best for your purposes would probably be the cache directory.
That one isn't located on the sd card but it's the only option you have.
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Well, the cache directory is just in the home directory and probably not big enough. I don't even need write access, just read access for now, as the user is putting the files there manually.
Until I have found a workaround, I am putting the files in Pictures.
At least for the Aquaris, the home partition is too small to store any serious map files, they can easily be a few GB.
nikwen said:
Ubuntu prevents file system access to any other location than your own data, cache and config directories by design. That decision was made to improve the security of the system.
However, as noted, you do have write access to three directories:
Code:
~/.local/share/package.name (for user data)
~/.cache/package.name (for caching)
~/.config/package.name (for config files)
The directory which would be best for your purposes would probably be the cache directory.
That one isn't located on the sd card but it's the only option you have.
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Sadly, I don't see many options here.
The only one which I can think of is the following: Ask your users to download the terminal app and copy over a command which either creates a (persistent) symbolic link from /home to their data directories on their sd cards or mounts the said folders in their home directories (the latter wouldn't be persistent after a reboot).
You still have to check out if that works but I'm confident that at least the mount scenario works.
Otherwise, I believe this would be a good question for the Ubuntu Phone mailing list where the OS developers hang out, too: http://launchpad.net/~ubuntu-phone.
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