Database Info

Need help with vold.conf for cupcake apps to sd

I am trying to work with haykuro to get apps on sd for his cupcake roms, but I ran into a problem. They replaced mountd with vold, and there is no known documentation on how to format the config file. This does not seem to be the same vold that is used on SUN or other unix operating systems. If anyone has any useful info, please share it with me so I can look into this further.

Maybe this will get you started...
*EDIT* didnt read your post correctly... Didnt see that it was not related to the Sun version.
Darkrift,
Maybe the vold.conf in the android system is similar to the vold.conf in my Solaris 10 Sparc Server.....
Code:
> > For Solaris 8, you have to fake a change on the vold.conf
> > configuration file, otherwise the HUP signal is ignored:
> >
> > touch /etc/vold.conf
> > + pkill −HUP vold
>
> I stopped vold & commented out the one /etc/vold.conf line:
> # use rmdisk drive /dev/rdsk/c*s2 dev_rmdisk.so rmdisk%d
If you want vold to automatically mount an usb mass
storage device on a reboot (or a re−start of vold, or the above
mentioned touch / SIGHUP sequence), you have to make sure to remove
the comment character from the "use rmdisk" line in /etc/vold.conf.
Study some of the Sun Solaris docs I have listed below and maybe you will find the right recipe you are looking for...
Sun Solaris USB Flash Drive Mount Command
Solaris 10 - System Administration Guide - Devices and File Systems
Hope this helps...
I'm on Gtalk as AndroidSamurai if you have any questions.
While I'm at it, this is the command to mount a floppy in Solaris...
Code:
mount -f pcfs /dev/diskette /mnt
/mnt is the mount point

Here is what is currently in the file:
Code:
## vold configuration file for Sapphire
volume_sdcard {
## This is the direct uevent device path to the SD slot on the device
media_path /devices/platform/msm_sdcc.2/mmc_host/mmc1
emu_media_path /devices/platform/goldfish_mmc.0/mmc_host/mmc0
media_type mmc
mount_point /sdcard
ums_path /devices/platform/usb_mass_storage/lun0
}
I tried adding:
Code:
volume_apps {
## This is the direct uevent device path to the SD slot on the device
media_path /dev/block/mmcblk0p2
media_type mmc
mount_point /system/sd
}
with no luck. And yes, I tried doing the media_path in the same format as the first one, which also did nothing.

Would the "mount_point" not be "/sdcard"?
I cannot work the terminal on my G1 bc of the keymapping error preventing me from using "/"...
Would it not be:
Code:
media_path /dev/block/mmcblk0p1
seeing that a fat partition(vfat) would be "p0" ?
Have you tried looking at "vold/mmc.c and vold/mmc.h" ?
Also try looking at the following:
Code:
vold/volmgr_ext3.c
vold/volmgr_ext3.h
vold/volmgr_vfat.c
vold/volmgr_vfat.h
If you would please e-mail me the vold.conf in a zip archive so I can play around with it a little...
Sorry, my resources are a little bare at the current time due to a surge knocking out all my equipment.
Email Me
or find me on GTalk under androidsamurai.....

No, i am trying to add apps to sd, which go in /system/sd/app. this would mount my second partition (ext2) /system/sd

Let me also state that the top part is working. that is what loads the sdcard to /sdcard. what I am trying to do is load the second partition to /system/sd by adding a *second* block to the file, which is not working.

Hi Darkrift,
I don't have a second partition on my sd card nor have I installed any of the cupcake builds so I can't test my thoughts myself but thought I'd share them with you...
Have you tried browsing to the directory referenced by the original vold.conf? I was just wondering how this structure compares to a device using a partitioned sd card? Maybe a comparison would give us some clues as to how the new volume manager works.
Mine looks like this:
sys/devices/platform/msm_sdcc.2/mmc_host:mmc1/mmc1:d516
With no other similarly name directories below the msm_sdcc.2 level.

Why don't we use Fat32 partition as extra memory? why can't we run application from a Fat32 partition?

#1 FAT32 doesn't support case-sensitivity, and that is enabled on the internal FS's
#2 extfs is way better than FAT
#2 FAT sucks

@wellsie: I think the problem is the name I am giving it "volume_apps {
" but if i change it to volume_sdcard { like the first one, it adds those config options to teh top block. Also I have tried adding all different versions of the media path (in /dev, in /system/devices and more) with no luck.
@funbacon: Joushou's ideas make sense, but neither of those are the reason. Each application installed on the G1 has an owner, group and set permissions. That is part of the "sandbox" that keeps apps from accessing each others files. Fat has no permissions, so an app on fat would not be able to have the needed permissions to be used.

Oh yeah, permissions aswell
I have been too long in unix, so i just expect that to be there
But i believe that fits under the "FAT sucks" category

I agree with that one

C'mon. I know someone has gotta have some ideas or maybe know how to browse the source and figure stuff out more than I could. I tried checking out the source but its fairly foreign to me. I know a little scripting, but not much as far as coding goes. I really would like to help get apps-to-sd working in cupcake but this is a major stumbling block for that.

I just want to say that even i am not proficient on this type of stuff i voluntere to test whatever setup you come up with.
I really apreciate your work on this as this is the only reason I have not moved to haykuros or anybodys cupcake build.
So thanks tanks to every body for pitching in.
oh by the way, If you set it up i will donate to the cause!!!!!

I'll try and look at the code over the weekend...family time comes first though so it may have to wait until next week when I'm at work ;-)

I think the main problem is the naming convention for a new "block". sdcard is already in use, and adding a second one just adds to the first one. I think there might be "sdcard2" or something else that it is expecting. I tried just naming it whatever I wanted hoping that would work but it didnt seem to.

im with carlos im not a good with all that code stuff, but im down to test whatever u come out with,
also for i heard haykuyo is coming out with a fix for the physical keyboard soon

If you are speaking about "Keyboard Fix" in the terms of the Keyboard Mapping being messed up, then chack out the first post of the Sapphire/Magic G1 Port thread... Keyboard mapping has been fixed.
I honestly cannot believe that Google hasn't had any hits on the android site about this problem yet...

Instead of partitioning, maybe we can try this other method for apps to sdcard.
http://forum.xda-developers.com/showpost.php?p=3402719&postcount=683
http://forum.xda-developers.com/showpost.php?p=3402947&postcount=687
This method creates an ext2 filesystem object as a file under the fat32 filesystem so there would be no need to partition.
I'm doing my taxes today, but if I get a chance to play around with it, I'll try to implement this tomorrow. Looks pretty straightforward.

well, nobody would know about this problem unless they are breaking the rules. A, having a rom which we should not have, and B, making changes to the OS and "hacking" it to read apps somewhere its not supposed to. Android should not have 2 partitions, so this is not something they would even answer.

[HOWTO] Running debian via chroot on OO

This tutorial is based on this one for G1: http://www.saurik.com/id/10
Hi,
I'll show you how to run debian in chroot on our optimus one. It wont affect android in any way, and they can run simultaneously, side by side. You are only running bash from debian, not its kernel or any other low-level part. But you can use debian's programs.
Requirements
* Linux on your pc or in virtual machine
You need debootstrap to make debian image, so you need debian distro (maybe in *buntu it is too, but I am not sure). You dont need GUI, bash is all you need.
* Busybox(-> rooted phone)
Most custom roms comes with busybox, I am not sure how about store ROM.
* Terminal emulator on phone and/or ADB
I suggest you to make sure you have adb, because you dont wanna write it all on small touch keyboard.
Some knowledge about linux systems
If you are following this tutorial only because you want to /flex on your friends and you dont know anything about linux, then you really _should_ stop reading this tutorial.
I also recommend you to have a2sd, so we can put debian image on its partition, when it is on sdcard main partition, it _may_ cause some problems with usb mass storage.
So, lets start.
1. Getting debian image
Boot into debian and get bootstrap tool:
Code:
apt-get install debootstrap
Now, create an empty disk image, I'd say minimum size is about 150mb, but I recommend you use more:
Code:
dd if=/dev/zero of=debian.img seek=*size_in_bytes* bs=1 count=1
You need to create ext filesystem in image with this tool(you can try it with "sudo" if you have problems):
Code:
mke2fs -F debian.img
Image is ready now, now lets mount it so we can install debian into it:
Code:
mkdir debian
mount -o loop debian.img debian
Debootstrap tool will do all the work for us. You can try to use squeeze instead of lenny or download it from your country's mirror. "--variant=minbase" argument will install just base system with apt-get and only few other packages. (This also may need sudo)
Code:
debootstrap --verbose --arch armel --foreign lenny debian http://ftp.cz.debian.org/debian
umount debian
2. Mount the image
Now, we will use ADB shell to mount the image and finish debian installation. Do not forget to write "su" before you start, we need root for this.
You need to decide where to put debian.img. I suggest you to put it on a2sd partition, which is system/sd, so :
Code:
cp /sdcard/debian.img /system/sd
export kit=/system/sd
Our mount point will be /data/local/mnt, so lets make some variable to make it easier:
Code:
export mnt=/data/local/mnt
busybox mkdir -p $mnt
We also need to set these enviroment variables, and we can also make alias for busybox so we dont have to write busybox all the time.
Code:
export PATH=/usr/bin:/usr/sbin:/bin:$PATH
export TERM=linux
export HOME=/root
alias _=busybox
Now we need to create loop device for image:
Code:
_ mknod /dev/loop0 b 7 0
And if nothing went wrong, you should be able to mount image now ("mount: no /etc/mtab" is normal) :
Code:
_ mount -o loop,noatime $kit/debian.img $mnt
3. Finalizing installation of debian
With mounted image, we can proceed to second stage of debian bootstrap:
Code:
_ chroot $mnt /debootstrap/debootstrap --second-stage
If you want install some packages with apt-get, you also need to add repo to sources.list. Of course, if you downloaded squeeze instead of lenny, you need to change "lenny" to "squeeze"
Code:
echo 'deb http://ftp.cz.debian.org/debian lenny main' >$mnt/etc/apt/sources.list
Set correct DNS servers - debian can't take them from Android.
Code:
echo 'nameserver 4.2.2.2' >$mnt/etc/resolv.conf
Done, installation over.
4. Running debian bash
To get to debian bash, use this command. You can try "cat /etc/issue.net" or "uname -a" so you can see its really debian.
Code:
_ chroot $mnt /bin/bash
But its not all yet, you need to mount some things for debian:
Code:
mount -t devpts devpts /dev/pts
mount -t proc proc /proc
mount -t sysfs sysfs /sys
Now link mtab to /proc/mounts. You need to do this only once.
Code:
rm -f /etc/mtab
ln -s /proc/mounts /etc/mtab
And if you want to use ssh server to log in into debian, you also should set root pass:
Code:
passwd root
5. Installing packages
First, you need to update packages list:
Code:
apt-get update
and now you can install whatever you want with "apt-get install"!
6. Finishing
I suggest you to write some .sh script so you can mount it all with one command, for example something like this: http://pastebin.com/VT6272d5
What packages have you tested?
sshd - works great, you can connect to phone via putty or ssh
mc - works, but phone screen is to small
gcc-avr - if you are programming for avr microcontrollers, you can compile it on your phone
netcat - telnet connection
git-core - works great
htop - you can see this on screnshot below
apache2 - works like a charm
xfce4, Xorg server and tightvncserver - working but slow, see screenshots
gnash - working but slow, see screenshots. This is the only option how to run flash content on optimus one xD
Iceweasel - if you are using vnc server, you can browse web pages
gcc, g++, autoreconf, cmake and whatever else is needed to build mangos - working
mysql-server - you have to set "user = root" in /etc/mysql/my.conf, but works
MaNGOS - http://getmangos.com/ takes long to build, but works! See this post and also this one.
..and maybe some more which I dont remember.
Hope this tutorial helped you

I'll try bootstrapping debian when I figure out what the hell is wrong with my system. I can't download files from ftp (but I can with wget and other progs. just not with pacman, debootstrap, and the like).

debian on optimus v
searched around to avoid multiple posts, and found this.
I've been running chroot debian on my V as well, squeeze then sid now going back to squeeze.
the main problem I've encountered was in the "debootstrap --second-stage", which generally froze at "I: configuring sysvinit". I thought that was from overloading the CPU, but turns out android init doesn't create /dev/initctl like debian does, so debootstrap hangs waiting for a response reading/writing /dev/initctl
I didn't have that issue using SL4A's shell instead of android terminal.
being a bit of a 'noid, I have used "mknod /dev/initctl p" in the chroot before running "debootstrap --second-stage" since reading of that solution. not sure if it's making much difference, because that didn't fix the issue before I found SL4A and was still using android terminal for shell functions.
I like xfce4 as a window manager in the VNC, it's small but still functional.
I did a bit of things different than saurik, but used his guide extensively, along with much googling for other deb->droid ports.
my chroot runs in the android root directory with bind-mounts since the custom kernel I like doesn't include unionfs. I also directly use an ext4 2nd partition on the SD rather than a loop-mounted filesystem image. (yes, ext4 journals will eventually frag my SD but the cost of another is worth the crash-resistance to me.)
my short-term goal is to mix inits between the two os's and run X through an android app frontend to avoid the framebuffer copy lag from the VNC. my 3 main reasons for debian on the phone are program development (works currently,) flash (actually gnash, and needs a working full-speed access to framebuffer, not working yet,) and emulators for J2ME and MAME (same boat as flash.)
so far trying to run X directly blanks my screen and forces a battery pull to get it back, so kinda giving up that route for the moment.

so installing Archlinux on O1 must be possible? how?

pymebrahimi said:
so installing Archlinux on O1 must be possible? how?
Click to expand...
Click to collapse
All must work, as long as they support running on ARM. AFAIK Arch doesn't have an (official) ARM port. You can try Arch Mobile though

This command fails me
Code:
_ mount -o loop,noatime $kit/debian.img $mnt
The error I get is no device or file exists.
Tried creating more number of loop devises too. Still it didn't work. I am using cyanogemmod 2.3.3 ROM.

onehomelist said:
This command fails me
Code:
_ mount -o loop,noatime $kit/debian.img $mnt
The error I get is no device or file exists.
Tried creating more number of loop devises too. Still it didn't work. I am using cyanogemmod 2.3.3 ROM.
Click to expand...
Click to collapse
What is the exact wording of the error?

The exact error that I get:
Code:
# busybox mknod /dev/loop0 b 7 0
# busybox mount -o loop,noatime $kit/debian.img $mnt
mount: can't setup loop device: No such file or directory

Instead of using $kit/debian.img, try manually pointing to the debian image.
For example, if you have it on the sdcard's debian folder:
Code:
/sdcard/debian/debian.img

That too didn't work.

make sure that debian image is where it should be. Also try to "ls /dev/" and look for loop0 - i had some problems with loop devices on mik's 2.3, but I did not really solved it, because I went back to froyo after while.

The loop0 device exists is /dev. As you have experienced same issue on the same ROM, I am convinced that its a ROM issue.

I just tried to install xorg, xfce4 & tightvncserver - everything work just fine, although its kinda slow

ext partition instead of loop filesystem
Tasssadar said:
I just tried to install xorg, xfce4 & tightvncserver - everything work just fine, although its kinda slow
Click to expand...
Click to collapse
I think it runs faster from a sdcard partition than a loop filesystem, if I remember right. I tested a loop-mounted preconstructed debian img from some tutorial for another device before debootstrapping my own.
partition your card with a second partition, ext2 if you're worried about journalling wearing out your sd, or ext4 if you're more worried about corrupting your precious debian filesystem in a crash or unclean umount. gparted in ubuntu seemed to work well for me.
resize your ntfs partition instead of deleting it or android may complain.
with your debian img mounted as a loop filesystem on a linux box at the same time as your new partition, you can copy everything from the img to the ext partition by:
Code:
cp -av /path/to/loopmountedimg/* /path/to/extpartition
if you replace the loop-mounting code in your boot script with a vold mount of your ext partition, android is supposed to umount the partition cleanly on powerdown or reboot.
on my optimus v, the mount looks like the following in my boot script (I'm posting the comments too for info)
# mount 2nd sdcard partition from vold, should prevent dirty unmount at reboot
# if your linux is on a different partition than 2, substitute that number for the 2 in .../vold/179:2 below
# first unmount it; if not already mounted, system will echo 'umount: can't forcibly umount /dev/block/vold/179:2: Invalid argument' but this isn't an error to worry about
Code:
umount -l /dev/block/vold/179:2
mount -o noatime,exec,suid /dev/block/vold/179:2 /$mnt
maybe someone here can use this info.
also, for anyone who wants to save some hours and bandwidth, I have a basic squeeze debootstrap uploaded to 4shared.
it shouldn't be missing any of the readme's or licensing docs, so it should be GPL ok AFAIK.
resolv.conf and sources.list are already configured for 3g access and the main Debian repository, so it's pretty much plug-n-play.
no extra packages. you'll need to apt-get tightvncserver and a window manager unless you just want the bash shell.
the first time you chroot in, you should use passwd to set a root password, and adduser to get a non-root account on there.
the only glitch is that I accidentally tar'd it into a compressed folder; so you can't just untar it into the ext partition, it needs unpacked with an archive manager. sorry!
here is the filesystem image
uncompressed, 9645 items, totalling 264.3 MB
compressed, 116.3 MB (121929580 Bytes)

Tried to put it on ext2 partition without image, its a bit faster but still very slow.
But i took some screenshots this time. You can see flash (well, gnash) player on optimus one working on last screenshot
And I have one question: is debian using its own libc or android's bionic?

Tasssadar said:
Tried to put it on ext2 partition without image, its a bit faster but still very slow.
Click to expand...
Click to collapse
guess I'm biased, first linux I used was on a 100MHz pentium 1, so this handheld flies by comparison.
But i took some screenshots this time. You can see flash (well, gnash) player on optimus one working on last screenshot
Click to expand...
Click to collapse
I could only get gnash to play ads. boo. froze up iceweasel every time I tried to open a flash video. what browser are you using? oh, man, it's iceweasel, isn't it?? also, chromium just refused to start on my optimus.
And I have one question: is debian using its own libc or android's bionic?
Click to expand...
Click to collapse
pretty sure it's standard debian libc. you could integrate the android toolchain if you were so motivated, probably.

bigsupersquid said:
I could only get gnash to play ads. boo. froze up iceweasel every time I tried to open a flash video. what browser are you using? oh, man, it's iceweasel, isn't it?? also, chromium just refused to start on my optimus.
Click to expand...
Click to collapse
Chromium does not work for me, too.
Well, it froze for me too, but after while it at least got to show what you see on the screenshot
bigsupersquid said:
pretty sure it's standard debian libc. you could integrate the android toolchain if you were so motivated, probably.
Click to expand...
Click to collapse
I was just thinking if this is possible, then normal android aplication could have libc included, if its needed.

Do you know MaNGOS? It is open-source server for World of Warcraft (for more info go to http://getmangos.com/). I just compiled it and I run it on my optimus one. And guess what - without world db, its really fast! I am extracting UDB to database right now, I will post some screenshots and results with full-featured db soon.
And thats why I love linux and android

I got no words to describe my eyes when reading that at the moment.

So, what you might wanna know if you wanna try it too:
All packages needed for mangos to compile are working good, except for mysql server: you need to set "user = root" in my.cnf - it is located in /etc/mysql/ - because you cant put any root rights to any other user than root, so mysql user cant create tcp socket.
You will most likely need swap file - optimus has plenty of RAM, but yet not enough. All you need is to compile kernel with CONFIG_SWAP=y and follow this tutorial: http://www.cyberciti.biz/faq/linux-add-a-swap-file-howto/. 512mb swap is enough. Just for the record, swap is working on optimus one, I think nobody tried it here yet.
Now as for the compilation of mangos, it is mostly working as it is, only problems are intel tbb library and g3dlite library.
TBB is not available for arm yet, so you need to compile without it. Use -DUSE_STD_MALLOC=0 in cmake line.
As for the g3dlite, things are little bit more tricky - you need it, and there are some asm() instructions in it, which are different for arm. I only commented them, because I dont know assembler: https://github.com/Tasssadar/mangos-arm/commit/67c442fa0c10e82b282b83a8fe485588f8786e12
I have no idea how it can even work without all that code in g3dlite, but it just does.
You can use scriptdev2 from its git, theres no problem in it.
Thats all, after that just "make" and get something good to read, because it will take really long. At least 5 hours for compilation and nearly hour and a half for linking of scriptdev2 and mangosd binary.
Creating of databases is just like on normal pc, so I just skip it...same goes for dbc files, maps and vmaps.
Loading of mangos takes around 4 minutes with full-featured db. mangos then takes around 180mb of ram and cpu usage is...surprisingly low, considering the fact that our cpu does not have hw float operations. I tried to clear Azjol Nerub instance (well, solo with gm character) and maximal cpu usage was 60%, when fighting a boss with lots of spawns. I could imagine some 5-man dungeon run would be just fine
Also, you will get slight lag when moving into new location, when phone loads map files from sdcard.
Thats all, see screenshots

[GUIDE] Creating and using filesystem images on Android

Hey all, This is my first post on the forum, so I thought I'd make it a guide.
I've run into a few roadblocks with installing some development tools like python and stuff, so I figured I'd try and make a filesystem image to hold all of it, what with Android preventing executables on your SD card from actually executing. You should NOT try and use this for freeing up space by moving apps to it. That just breaks things.
Things to know
A mount point is where you access the contents of a filesystem through.
A filesystem is basically a virtual disk.
I'm not responsible for your phone melting into a pool of acid or anything else you want to blame me for. You executed the commands, not me.
If there's been guides for this already, I didn't find them.
Playing with your system files is dangerous. Be careful
Playing with filesystems is even MORE dangerous. Don't do it unless you know what's going on.
Reversing and then combining two words in a sentence, then calling it a bit more dangerous is incredibly dangerous and can kill you. Don't do it.
As I said earlier: This is not intended to free up internal storage on your phone. It is intended to create extra space to put command-line executables.
This was created for those of us who have older phones that don't have a whole lot of internal storage. (Like the Milestone) This should also work on anything that meets the requirements listed below. I use it on a Motorola Milestone A853 running CyanogenMod 7.2.4f UMTS/SHOLES, and it took some tweaking, but it worked. Commands you put into your shell are marked with `bolded text and surrounded by back-ticks. Leave the back-ticks out. (`)`
Requirements! (obtained using `which <command name>` or a specified command)
Free space on your mSD
losetup (configuring loop devices)
mknod (creating loop devices)
mount (mounting filesystems)
mkdir (making directories)
su (root access)
umount (unmounting)
mke2fs (formatting)
Linux filesystem support (`cat /proc/filesystems | grep ext`)
Here we go!
This assumes you are going to use an ext4-formatted filesystem image mounted on /data/development/, with the image located at /mnt/sdcard/development.img. You WILL need to determine your phone's supported ext<num> filesystems using `cat /proc/filesystems | grep ext`. Choose the highest-numbered one.
Create the mountpoint, the image, and then format the image to ext4.
`mkdir /data/development/`​`dd if=/dev/zero of=/mnt/sdcard/development.img count=409600 bs=1024`​`mke2fs -l /mnt/sdcard/development.img -b 1024 -t ext4`​
Create the block device, set it to point at the image, then mount it.
`mknod /dev/block/loop250 b 7 250`​`losetup /dev/block/loop250 /mnt/sdcard/development.img`​`mount -t ext4 /dev/block/loop250 /data/development`​
Test it to see if it works.
`touch /data/development/testfile;ls /data/development/`​
Use it.
Unmounting (/!\ For connecting to a computer to avoid corruption /!\)
`umount /mnt/sdcard/development.img`​`losetup -d /dev/block/loop250`​
Well, that's all I've got. Suggestions and corrections, as well as good feedback are appreciated.
Some PAQs (Possibly Asked Questions)
Q: I'm getting some errors. Here they are: pastebin.com/some-errors
A: Great, I'll see what I did wrong, and if it's something on your end, I'll try and help you out.
Q: It dun werk
A: Tell me the errors instead of complaining about them. Just saying that does not help me and wastes my time and bandwidth.
Q: "No space left on device"; "Operation not permitted"; "No such file or directory"
A: SD card full; not root (or SD card is full, or something broke); Mount point doesn't exist or (if 'mount' returns that and the point exists) something not cool happened.

Usage guide on Non-Android devices
Some interesting bits of information for use on computers:
There's probably not an easy way to read/write/mount EXT2 filesystems on a Windows machine, so if you have a solution that's stable, go for it.
Linux computers definitely should support this, and I'm not sure about OSX computers, but in theory would work if you had the right things installed. iPhones ... well I have no idea what you'd do with it there.
Linux:
On the device:
THIS PART IS EXTREMELY IMPORTANT, NOT DOING THIS WILL RESULT IN BROKEN FILESYSTEMS!
`umount /mnt/sdcard/development.img`
`losetup -d /dev/block/loop250`​Plug your phone into your computer, making sure that the computer mounts it and reads it as removable media, and that the image is present.
On the computer: (Path of your user folder, and the mount point at which your device's SD is mounted can and very likely will vary from distribution to distribution. Check your paths.)
`mkdir /home/user/android-devtools/`
`mount -o loop /media/user/android-sd/development.img /home/user/android-devtools/`​Now, you can change things within the image as you normally would a file or folder. Be warned, sometimes doing this can create conflicts in the file permissions, so running the right commands on the phone to change the permissions as root (use `chmod` for the permissions) can save you boatloads of trouble getting things to work, or editing files.
Mac OSX might or might not be the same, but seeing as I haven't picked up an Apple computer since maybe 5 years ago, let alone attempted filesystem management, I just don't know.

[DEV UTILITY] Native rsync

If you haven't heard of rsync before, welcome. If you have, just skip to the end.
rsync is a pretty standard Unix utility that was originally for syncing a local and a remote filesystem. It it "smart" in that it only copies what it needs to, so you can (and I do) rsync your SD card to a computer on your desk that gets backed up regularly, and only send the changed files every time, not the whole 64 GB. It will work over ssh so you can even sync over the air securely. It is also a great tool for copying a Unix filesystem from one place to another, for example, copying your internal /data to a new 2 GB partition on your microSD (yes, foreshadowing).
For more, see http://rsync.samba.org/documentation.html
Installing:
extract the tar
copy rsync to /system/xbin/rsync
chmod 755 /system/xbin/rsync
I've been using it for a couple years, but it was a pain to build on Android with tons of patches needed, like "standard" keyboard-input libraries which aren't part of the Android libraries. With GPL requirements on rsync, I just couldn't reasonably maintain a "turnkey" build chain to be able to distribute a binary before.
Well, a lot of the changes I used to have to make are now in v3.0.1, that now configures and builds with the standard Android NDK, or directly in an AOSP-like build environment, like CyanogenMod 9, with the attached Android.mk.
Source code for rsync is available at http://rsync.samba.org/

You can do very fast backups of your /data and /system with rsync, which is nice when trying out new ROMs. You don't need to use something like the Hefe Hook kernel to do this, as long as your recovery will let you mount an ext2/3/4 partition that is big enough for the backup. 1 GB is generally big enough if you are just using internal flash.
Assuming you have a spare partition on your microSD, that it is formatted ext4, it has a "cm9-backup" directory you created, and that it gets mounted to /mmc0p4/, you can do a fast backup "snapshot" of your device by booting into recovery, getting in with adb, and doing something along the lines of:
Code:
mount -a
rsync -axvihP --delete /system/ /mmc0p4/cm9-backup/system/
rsync -axvihP --delete /data/ /mmc0p4/cm9-backup/data/
rsync -axvihP --delete /and-sec/ /mmc0p4/cm9-backup/and-sec/
Restore is the opposite, once /system, /data, and /and-sec (special directory in your microSD card's FAT partition) are mounted and writable
Code:
rsync -axvihP --delete /mmc0p4/cm9-backup/system/ /system/
rsync -axvihP --delete /mmc0p4/cm9-backup/data/ /data/
rsync -axvihP --delete /mmc0p4/cm9-backup/and-sec/ /and-sec/
Note that these paths are what I see on my phone using the Hefe Hook kernel and its configuration of TWRP. Your paths may be different. You don't need to mess with /and-sec/ if you know you don't have any apps moved to SD.
You can add --dry-run to the rsync command line before you commit to things to make sure the rsync command is doing what you would expect. The other flags I generally use are:
-a -- archive mode, recursively copy "everything"
-x -- one file system, don't descend into mount points
-v -- verbose
-i -- information on each file being copied
-h -- "human" readable output
-P -- show progress and allow for partial updates
--delete -- if the file isn't in the source and is in the destination, delete it form the destination as well​
As this is "real" rsync, you can look at the man page for more information.

also reserved

Dude awesome, I'll definitely use this on my other android devices. . Will make cloning my SD card simple.

Is it necessary to umount sdcard1 before running fsck_msdos

QSTN1: Is it necessary to umount sdcard1 before running fsck_msdos?
By doing so seems to break and remove some HomeScreen icons on some OS's where certain Apps have been 'Moved to SDcard'.
QSTN2: Does newer versions of Android OS (ie 5.0.2+) natively and automatically run fsck and fsck_msdos at boot-time on your FAT formatted plugin micro-SD card, or is it an add-on specific from various OEMs?
Most of you are probably very familiar with Windows ChkDsk.exe C: /f to repair damaged/corrupted SDcards.
You may have found that by removing your SDcard from your Android device and running ChkDsk under Windows, that you solved a lag problem with your Android device. By running ChkDsk on your SDcard, maybe prompted for you to 'Convert lost chains to files', and by fixing that, fixed my lag problem.
You may also have found that sometimes that's not enough, and you need to copy your whole SDcard over to a Windows folder, reformat your SDcard as FAT (same as it was before) and copied your data back. That certainly has been the case on one of my older and slower Android 10" tablets that some Apps like 'Screenshot Ultimate Pro' by 'Ice Cold Apps', as great as it is, sometimes corrupts my SDcard when I'm tapping around too fast.
Instead of having to take the SDcard out of my tablet each time I detected this problem, I needed to run fsck_msdos on the tablet itself, so I went through the motions and finally created a HomeScreen icon, where one single click will repair the SDcard and I could then get on with business.
TIP1: I've successfully created a HomeScreen icon using SManager by devwom by placing the following script under a 'scripts' folder I created under the default Home directory of SManager.
I also made sure that the script file had the appropriate (FULL) rights and that under Advanced, I made my 'Scripts' folder, SManager's Home-base.
My preferred location to place shell (.sh) scripts for SManager (Script Manager) by devwom:
/data/data/os.tools.scriptmanager/Scripts/
I used SMWidgets by devwom to create the HomeScreen icon for the script.
#!/system/bin/sh
# scr_FsCk_MsDos_on_MoXT1068_sdcard1.sh
# umount /dev/block/vold/179:65
fsck_msdos -y /dev/block/vold/179:65
echo .........
echo : Done! :
echo .........
NOTE: You can see in the script above, that I've commented out the umount command which seems to work whether or not the SDcard has been dismounted or not.
This is my main question I need answering, as around the traps, I see conflicting reports about dismounting first and I'd rather not have to do that if all works by leaving the SDcard mounted during fsck_msdos.
Thanks.

Hi, If I do this per adb shell as su I get the following error:
Code:
1|herolte:/ # fsck_msdos -y /dev/block/vold/public:179,1
fsck_msdos -y /dev/block/vold/public:179,1
stlog : disable(No such file or directory)
begin(dev:/dev/block/vold/public:179,1)
** fsck_msdos for samsung-mod version 1.1.1
** /dev/block/vold/public:179,1
exFAT signature in boot block: unsuported
end(ret:2, stderr:0, dev:/dev/block/vold/public:179,1), stat(dirs:(0/0), files:0)
Any advice please!