Hello folks,
on my HTC Desire with OpenDesire 3.5.2 I'm trying to install the dropbear ssh-deamon according to a german tutorial (I'm not allowed to put the link here... ).
It is on www and then android-hilfe.de and then, go /root-hacking-modding-fuer-motorola-milestone/14241-per-ssh-auf-den-milestone.html
I'm connected to the phone using adb and shell'd into.
Now, they say that I have to mount /system as read-write to put a file (dropbear) into /system/bin. The command is
Code:
mount -o remount,rw /dev/block/mtdblock3 /system
and results in no errors. mount then says:
Code:
rootfs on / type rootfs (ro,relatime)
tmpfs on /dev type tmpfs (rw,relatime,mode=755)
devpts on /dev/pts type devpts (rw,relatime,mode=600)
proc on /proc type proc (rw,relatime)
sysfs on /sys type sysfs (rw,relatime)
none on /acct type cgroup (rw,relatime,cpuacct)
tmpfs on /mnt/asec type tmpfs (rw,relatime,mode=755,gid=1000)
none on /dev/cpuctl type cgroup (rw,relatime,cpu)
/dev/block/mtdblock3 on /system type yaffs2 (rw,relatime)
/dev/block/mtdblock5 on /data type yaffs2 (rw,nosuid,nodev,relatime)
/dev/block/mtdblock4 on /cache type yaffs2 (rw,nosuid,nodev,relatime)
/sys/kernel/debug on /sys/kernel/debug type debugfs (rw,relatime)
/dev/block/vold/179:1 on /mnt/sdcard type vfat (rw,dirsync,nosuid,nodev,noexec,relatime,uid=1000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro)
/dev/block/vold/179:1 on /mnt/secure/asec type vfat (rw,dirsync,nosuid,nodev,noexec,relatime,uid=1000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro)
tmpfs on /mnt/sdcard/.android_secure type tmpfs (ro,relatime,size=0k,mode=000)
so in my opinion, /system shoult be writable.
But everything I try results in an "Out of memory" error: Creating directories, copying files - anything.
Only deleting files is possible: I backed-up and then deleted some ringtones from /system/media/audio/ringtones, and I'm also not able to copy the backup of them I did before onto the sdcard back into the directory again
I read in another thread, that the error "Out of memory" itself is a bug and should mean "No permission". But why don't I have permission?
df -h gives me
Code:
Filesystem Size Used Available Use% Mounted on
tmpfs 203.4M 0 203.4M 0% /dev
tmpfs 203.4M 0 203.4M 0% /mnt/asec
/dev/block/mtdblock3 250.0M 106.4M 143.6M 43% /system
/dev/block/mtdblock5 147.6M 53.9M 93.8M 36% /data
/dev/block/mtdblock4 40.0M 1.1M 38.9M 3% /cache
/dev/block/vold/179:1
3.7G 2.9G 744.3M 80% /mnt/sdcard
/dev/block/vold/179:1
3.7G 2.9G 744.3M 80% /mnt/secure/asec
so there definitively IS enough memory for a 720kB file.
Any ideas?
You can only write to system on the desire via adb from recovery.
If above post didn't explain it enough...
There is no write access to /system partition yet, except via a overlay file system. Have a search and you'll find, like everybody else.
thank you! Yes, that is the problem. I read this also somewhere, but didn't remember it.
I still cant write files even though im in recovery?
zoltrix said:
I still cant write files even though im in recovery?
Click to expand...
Click to collapse
Type "adb remount"
(Without "")
zHk3R said:
Type "adb remount"
(Without "")
Click to expand...
Click to collapse
Im trying to relfash my recovery and i keep getting the no space issue.
If i type in adb remount, i can no longer mount my sd card that is holding my image..
http://forum.xda-developers.com/showthread.php?t=805141
EDIT: If i figure out how to s-off my phone, will that fix it?
zoltrix said:
Im trying to relfash my recovery and i keep getting the no space issue.
If i type in adb remount, i can no longer mount my sd card that is holding my image..
http://forum.xda-developers.com/showthread.php?t=805141
EDIT: If i figure out how to s-off my phone, will that fix it?
Click to expand...
Click to collapse
Just follow the thread in Desire Android Development and you'll have S-OFF easy.
PRO TIP: Use a flash drive rather than burning the .iso on a CD.
Yea but, will i need s-off to flash this recovery?
I know s-off lets you do stuff within fastboot, but im not too sure what taht really means
zoltrix said:
Yea but, will i need s-off to flash this recovery?
I know s-off lets you do stuff within fastboot, but im not too sure what taht really means
Click to expand...
Click to collapse
nevermind, ive done my research and s-off fixed my problem!
details
could you please describe in a little bit more details how you have managed to write the /system mount point ?
thanks in advance ...
btw, there are o bunch of guys that want this answer
What? and Why?
I too would like to know more about writing to /system.
adb remount appears to switch the mount point from "ro" to "rw" (as shown with mount command) but I still get the same "Read-only file system" response when I try to adb push files.
What exactly is the issue here? Is it related to S-ON / S-OFF ?
What do I have to do to be able to write to /system?
(other than reboot into recovery; when I copy files in Recovery, they are gone after a normal reboot)
Thanks
I just downloaded this after finding it online. it says im missing the runtime. how do i fix this
Make sure you use the most recent version which can be found in the Android dev section on these forums.
DirkGently1 said:
Make sure you use the most recent version which can be found in the Android dev section on these forums.
Click to expand...
Click to collapse
I was on the SuperOneClick Android dev. page but it would not allow me to post as I am a horrible underling and have no privileges.
So if anyone can post it there or answer it here then this is the failure error I get for the device (A coby Kyros MID8024)
I have everything set up and the tablet is running android 2.2 all drivers and other files needed are installed.
Installed terminal emulator confirms NO SU allowed.
Getting mount path...
rootfs on / type rootfs (rw)
ubi0:rootfs on / type ubifs (rw,relatime)
tmpfs on /dev type tmpfs (rw,relatime,mode=755)
devpts on /dev/pts type devpts (rw,relatime,mode=600)
proc on /proc type proc (rw,relatime)
sysfs on /sys type sysfs (rw,relatime)
tmpfs on /mnt/asec type tmpfs (rw,relatime,mode=755,gid=1000)
none on /proc/bus/usb type usbfs (rw,relatime,devmode=666)
none on /dev/cpuctl type cgroup (rw,relatime,cpu)
/dev/block/mmcblk0p3 on /data type ext4 (rw,nosuid,nodev,relatime,barrier=1,data=ordered)
/dev/block/mmcblk0p2 on /cache type ext4 (rw,nosuid,nodev,relatime,barrier=1,data=ordered)
/dev/block/vold/179:1 on /mnt/nand type vfat (rw,dirsync,nosuid,nodev,noexec,relatime,uid=1000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,iocharset=utf8,shortname=mixed,utf8,errors=remount-ro)
/dev/block/vold/179:9 on /mnt/sdcard type vfat (rw,dirsync,nosuid,nodev,noexec,relatime,uid=1000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,iocharset=utf8,shortname=
FAILED
Thanks if anyone can assist.
I used the super 1click method to root. It failed the first time but I rebooted my tablet and ran the super1click a second time and it sucessfully rooty my tablet...now looking for instructon for installing market.
Vernox701 said:
I used the super 1click method to root. It failed the first time but I rebooted my tablet and ran the super1click a second time and it sucessfully rooty my tablet...now looking for instructon for installing market.
Click to expand...
Click to collapse
Why not just flash google apps? That should install the market or you could download the apk for the market directly. See this thread: http://forum.xda-developers.com/showthread.php?t=1231290 .
TUTORIAL - EVERYTHING ABOUT ADB - Fully Illustrated
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This will be part of a series of Tutorials compiled to better educate the Beginner-Intermediate users in XDA thread, and help them get rid of the "n00b" or "newbie" tag thrown at them!
1. WHAT IS ADB?
ADB or Android Debug Bridge is a command line program which is used to communicate with your Android phone (or an emulator used by programmers). The use of Adb for Android phone users ranges from using it as a tool to get the logcat- A realtime log of the Android system, which allows one to know the cause of any errors. It is very helpful to app hackers to know exctly what block of code does what, and to modify apps accordingly
2. HOW TO USE ADB - Running adb.exe
adb.exe is part of a package of tools called Android SDK or Software Development Kit. For users, the main applications useful for them are adb.exe, fastboot.exe and aapt.exe.
2.1 Installing adb.exe (Windows)
First, download the Android SDK package(exe file) from here The installer will prompt you to download and install the JDK (Java Development Kit) if you dont have it already installed
Next install the exe file and note the location where you install it to.
After install is over, use Windows explorer and navigate to the folder where you installed the SDK.
Double-click the SDK Manager.exe/SDK Setup.exe file at the root of the Android SDK directory.
This will open up the SDK Installation window, where you can choose from a list of packages to install
If you want to use only adb.exe and fastboot.exe, choose to install only the "Android SDK Tools" from the list (See fig 1 below)
That's it, adb.exe is now installed
Fig1:
Take a note of where you install it. It usually installs to a folder named Android-sdk-windows. Once you have it installed, you can copy the entire folder on a portable usb key/CD and use it on any other PC without a need to install it. I recommend that you make it a part of your Android CD (with rooting tools, unrooting tools, gold card etc).
2.2 Using adb.exe-Preparing your PC for running adb.exe quickly
Adding Adb to your Windows Path
Once installed, you should add the location of adb.exe to the* Windows Environment Path variable. To do that, go the subfolder of Android-sdk-windows where adb.exe can be found. Click on the Windows Explorer path displayed on Top, and copy the path to the Clipboard
Go to Start Menu, and Right click Computer, Choose Properties
Choose Advanced System Settings and then Environment variables
Now, add the Location you copied to the Clipboard earlier, to the end of the current path, after adding a ";"(without the quotes) to the end of the current path.
So, in my case, the current path shows:
c:\droidzone\windows; c:\droidzone\blahblah
It now becomes:
c:\droidzone\windows; c:\droidzone\blahblah;C:\Software\Phone\android-sdk-windows\tools
Hit Enter to everything.
From now, whenever you open a Command prompt in Windows, you will be able to execute Adb and Fastboot from there without needing to navigate to the folder where they are installed.
Next step: Elementary Adb commands
Don't forget to Hit the Thanks button to let me know that my posts helped you!
Elementary Adb commands
Ok, now that you've got adb all setup and prepared your computer to use it, you're ready to learn some basic adb commands. I'll be teaching some of them in this section.
Understanding how adb and the shell works
Let's first check if adb is working by asking it to communicate with our phone. Connect the phone with a usb cable to the PC. Note that you should have installed the HTC drivers already (They come with HTC Sync)
From your Windows Start Menu, Click on Run, then type the following and press enter. That should open a command shell:
Code:
cmd
Once there, type out the following:
Code:
adb devices
This will display a list showing the connected phones with their serial numbers (and emulators-But let us not worry about what these are, right now)
Great, now we have confirmation that adb is working! We're now ready to issue our basic commands.
First thing to note is the basic command to enter the Android custom linux shell. Like Windows has cmd.exe to enter the dos shell, the graphical eyecandy with Sense overlay that you see on your device has a custom linux kernel running, so basically the language of its shell is the Linux shell language.
Accessing the Linux terminal (adb shell) is what we do to issue commands. To enter the shell of our device, the basic command is:
Code:
adb shell
Immediately, you will get a prompt like this:
Code:
sh-3.2#
Now we can type out any (most) linux commands and these will be executed in our device.
The file system on Android is laid out over MTD partitions in your device's NAND (Internal memory), and the SD card. The Nand is strictly organized in a Linux system with Linux file permissions and ownership rights (Just know that these exist, for now)
So, right now, you will be dropped in the "root" of the filesystem, from where you can navigate to other places.
Note! An important difference between Linux and Windows is that while Windows uses the Backslash (\), Linux/Android uses the forward slash (/) to depict directory hierarchies. Another one you shouldnt forget is that in Linux/Android, a file named boot.img is different from Boot.img, BOOT.IMG and BoOt.img, while on Windows, they are all the same.
Click to expand...
Click to collapse
My tutorial is about adb commands, and not linux, so I'll give only a short summary of elementary linux commands below. I will expand the list and explanation for this at a later date if you require it:
pwd-Shows the current working directory
cp-copy a file
mv-move a file (copy a file and then delete the original file)
chmod-set file permissions
chown-set file ownerships
rm-delete a file
cd-change directory
rmdir-delete a directory
Click to expand...
Click to collapse
Elementary Adb commands
Installing applications with adb
You can install any apk from your PC to the phone very easily. Open a cmd shell, and then type in:
Code:
adb install
followed by a space. Now drag an apk file in Windows explorer to the shell we have opened. Immediately, the path of the file becomes inserted in our prompt that it becomes:
Code:
adb install C:\Desktop\TitaniumBackup.apk
assuming that the file TitaniumBackup.apk was present in the location C:\Desktop. Hit enter and you will notice that it gets installed.
Transferring files to the sdcard without connecting the device as Disk drive:
Code:
adb push C:\Desktop\TitaniumBackup.apk /sdcard/
will trasfer the file C:\Desktop\TitaniumBackup.apk to the root (main) directory of your sdcard. Likewise, you can transfer any file from the PC to any location on your device.
Eg: I want to transfer a file called wallpaper.zip to a location /data/local. The command would be:
Code:
adb push C:\Desktop\wallpaper.zip /data/local/
Contd..
Don't forget to Hit the Thanks button to let me know that my posts helped you!
More elementary adb commands:
Getting a file from your phone to your PC:
To get a file /system/etc/init.d/01data to your PC, you would type out the following:
Code:
adb pull /system/etc/init.d/01data
which will transfer the spcified file to the location on your pc where you have opened the cmd.exe shell.
Mounting the system partition as Read Write to transfer files to your /system partition:
Method 1:
Code:
adb remount
Method 2:
This can also be accomplished with the more advanced mount command in the adb shell. First we need to know the mount point of the partitions.
Type:
Code:
adb shell
mount
For me, it displays:
Code:
rootfs / rootfs rw,relatime 0 0
tmpfs /dev tmpfs rw,relatime,mode=755 0 0
devpts /dev/pts devpts rw,relatime,mode=600 0 0
proc /proc proc rw,relatime 0 0
sysfs /sys sysfs rw,relatime 0 0
/sys/kernel/debug /sys/kernel/debug debugfs rw,relatime 0 0
none /acct cgroup rw,relatime,cpuacct 0 0
tmpfs /mnt/asec tmpfs rw,relatime,mode=755,gid=1000 0 0
tmpfs /mnt/obb tmpfs rw,relatime,mode=755,gid=1000 0 0
tmpfs /app-cache tmpfs rw,relatime,size=8192k,mode=755,gid=1000 0 0
none /dev/cpuctl cgroup rw,relatime,cpu 0 0
[B]/dev/block/mtdblock3 /system yaffs2 ro,relatime 0 0[/B]
/dev/block/mtdblock4 /cache yaffs2 rw,nosuid,nodev,relatime 0 0
/dev/block/mtdblock5 /system/data yaffs2 rw,nosuid,nodev,noatime,nodiratime 0 0
/dev/block/mmcblk0p2 /data ext4 rw,nosuid,nodev,noatime,nodiratime,commit=50,bar
rier=0,stripe=64,data=ordered,noauto_da_alloc 0 0
/dev/block/vold/179:1 /mnt/sdcard vfat rw,dirsync,nosuid,nodev,noexec,relatime,u
id=1000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,iocharset
=iso8859-1,shortname=mixed,utf8,errors=remount-ro 0 0
/dev/block/vold/179:1 /mnt/secure/asec vfat rw,dirsync,nosuid,nodev,noexec,relat
ime,uid=1000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,ioch
arset=iso8859-1,shortname=mixed,utf8,errors=remount-ro 0 0
tmpfs /mnt/sdcard/.android_secure tmpfs ro,relatime,size=0k,mode=000 0 0
sh-3.2#
Note that the entry for system partition shows:
/dev/block/mtdblock3 /system yaffs2 ro,relatime 0 0
The ro means that /system is mounted as RO-i.e Read Only. The whole line means that the Nand MTD block device on /dev/block/mtdblock3 is mounted on the mount point /system, to use technical jargon.
We need to mount it as RW (Read Write)
The command is:
Code:
mount -o rw,remount /dev/block/mtdblock3 /system
This essentially mounts the /system as Read Write so that you can write to it (Normally you cant write to the /system partition), which is what "adb remount " also does. However the commands above can be executed from a Terminal Emulator application too.
Next: Getting an Adb logcat
Don't forget to Hit the Thanks button to let me know that my posts helped you!
Getting an adb logcat
Many a time, you might have heard people telling you to get a logcat to report your error with a Rom installation.
What is a logcat?
A logcat is a report from the Android logging system, which takes place in the background the whole time your phone is on. It starts the moment you switch on the phone, and continues till you shut it down completely. This log is extremely useful for finding out what went wrong with your system. It is useful to find out why your phone is having bootloops or force closes. It is infact useful for all errors!
How to get the logcat?
Basically, you can view the logcat log with the following command:
Code:
adb logcat
But that means getting overwhelmed by an endless haze of output flowing at a rate that you cant read and will overwhelm your command shell's capacity very soon.
So the system we normally use is to output the log to a file from which we can read later. This is done by the following command:
Code:
adb logcat > log.txt
My Technique
As a Rom developer and apk patcher, I have to constantly check for errors in my system. So I've devised an ingenous method to easily log logcat, and view them readily. I use a combo of commands executed in succession:
Code:
adb kill-server
echo "" > log.txt
start log.txt
adb logcat > log.txt
These commands essentially create a blank file named log.txt in the same path as the command shell you've opened. Then, it opens the file log.txt (which is blank at this point of time. Then it logs logcat output to that file. Once you refresh the opened file, it will show the output of logcat to this point of time. Refresh it once again, and it updates once more. You should install Notepad++ and associate .txt files with it, to get best results.
Instead of executing these four commands, you can download the batch file getlog.cmd and extract it from the zip file to the folder containing adb.exe. Once you type in the following command (from anywhere in Windows), you will achieve the same result as typing the four commands as above! Ingenious, eh?
Don't forget to Hit the Thanks button to let me know that my posts helped you!
Summary of other adb commands
The following is the partial list of commands supported by adb. You can obtain this list by the following command:
Code:
adb /?
Code:
C:\Users>adb /?
Android Debug Bridge version 1.0.26
-d - directs command to the only connected USB devic
e
returns an error if more than one USB device is
present.
-e - directs command to the only running emulator.
returns an error if more than one emulator is r
unning.
-s <serial number> - directs command to the USB device or emulator w
ith
the given serial number. Overrides ANDROID_SERI
AL
environment variable.
-p <product name or path> - simple product name like 'sooner', or
a relative/absolute path to a product
out directory like 'out/target/product/sooner'.
If -p is not specified, the ANDROID_PRODUCT_OUT
environment variable is used, which must
be an absolute path.
devices - list all connected devices
connect <host>:<port> - connect to a device via TCP/IP
disconnect <host>:<port> - disconnect from a TCP/IP device
device commands:
adb push <local> <remote> - copy file/dir to device
adb pull <remote> [<local>] - copy file/dir from device
adb sync [ <directory> ] - copy host->device only if changed
(see 'adb help all')
adb shell - run remote shell interactively
adb shell <command> - run remote shell command
adb emu <command> - run emulator console command
adb logcat [ <filter-spec> ] - View device log
adb forward <local> <remote> - forward socket connections
forward specs are one of:
tcp:<port>
localabstract:<unix domain socket name>
localreserved:<unix domain socket name>
localfilesystem:<unix domain socket name>
dev:<character device name>
jdwp:<process pid> (remote only)
adb jdwp - list PIDs of processes hosting a JDWP transport
adb install [-l] [-r] [-s] <file> - push this package file to the device and i
nstall it
('-l' means forward-lock the app)
('-r' means reinstall the app, keeping its data
)
('-s' means install on SD card instead of inter
nal storage)
adb uninstall [-k] <package> - remove this app package from the device
('-k' means keep the data and cache directories
)
adb bugreport - return all information from the device
that should be included in a bug report.
adb help - show this help message
adb version - show version num
DATAOPTS:
(no option) - don't touch the data partition
-w - wipe the data partition
-d - flash the data partition
scripting:
adb wait-for-device - block until device is online
adb start-server - ensure that there is a server running
adb kill-server - kill the server if it is running
adb get-state - prints: offline | bootloader | device
adb get-serialno - prints: <serial-number>
adb status-window - continuously print device status for a specifie
d device
adb remount - remounts the /system partition on the device re
ad-write
adb reboot [bootloader|recovery] - reboots the device, optionally into the boo
tloader or recovery program
adb reboot-bootloader - reboots the device into the bootloader
adb root - restarts the adbd daemon with root permissions
adb usb - restarts the adbd daemon listening on USB
adb tcpip <port> - restarts the adbd daemon listening on TCP on th
e specified port
networking:
adb ppp <tty> [parameters] - Run PPP over USB.
Note: you should not automatically start a PPP connection.
<tty> refers to the tty for PPP stream. Eg. dev:/dev/omap_csmi_tty1
[parameters] - Eg. defaultroute debug dump local notty usepeerdns
adb sync notes: adb sync [ <directory> ]
<localdir> can be interpreted in several ways:
- If <directory> is not specified, both /system and /data partitions will be u
pdated.
- If it is "system" or "data", only the corresponding partition
is updated.
I will add notes for these if you require them.
See the next post for Kernel errors..
How to get Kernel error messages
You can get debug messages from a running kernel with:
Code:
adb shell
dmesg
If you have reboots due to kernel panic, you should make users capture the last_kmsg log from /proc immediately on the reboot.
Note that dmesg can be disabled by the kernel maintainer, and hence some roms/kernels may not support the command.
Code:
adb shell
cat /proc/last_kmsg > /sdcard/last_kmsg
Should be done immediately after the reboot..Otherwise it will just get overwritten by newer kernel message.
So in brief, if you'd like to look at what the kernel is doing right now (any errors etc), you should use dmesg. If you want to know why your kernel rebooted, use the file proc/last_kmsg
It's extremely useful!
Don't forget to Hit the Thanks button to let me know that my posts helped you!
Guys, part of the tutorial is over.. Hope it is helpful. Will add more useful and advanced stuff later.. Hope it helps the newbies and some more seasoned users.
Feel free to ask any doubt that you think is silly, without fear of being ridiculed or being asked to search the thread! It should be related to adb though!
Impressive tutorial. You'll get my thanks when im back at my home pc
Sent from my HTC Desire S using XDA App
Nice tutorial bro. shoud be on dev section...???
coolexe said:
Nice tutorial bro. shoud be on dev section...???
Click to expand...
Click to collapse
Thanks bro.. I thought that might scare away newbies, plus since I havent done any actual development..
Droidzone said:
Thanks bro.. I thought that might scare away newbies, plus since I havent done any actual development..
Click to expand...
Click to collapse
Hi,
there is lots of thread in dev. section which doesn't belong to development...anyway nice tutorial for noobs...if possible add QtADB tool...
EDIT: Added to my threads
Will add a GUI section. Good tip.. It's a very useful tool
Hi there.
Well this is a nice tut for android newbies like me
can you also add a basic symlinking tut? (especially how to symlink a folder to an already existing symlink )
thanks!
jesseuy said:
Hi there.
Well this is a nice tut for android newbies like me
can you also add a basic symlinking tut? (especially how to symlink a folder to an already existing symlink )
thanks!
Click to expand...
Click to collapse
Does this answer your query?
From http://uw714doc.sco.com/en/SDK_sysprog/_Using_Symbolic_Links.html
Code:
[B]Creating symbolic links[/B]
To create a symbolic link, the new system call [URL="http://uw714doc.sco.com/en/man/html.2/symlink.2.html"]symlink(2)[/URL] is used and the owner must have write permission in the directory where the link will reside. The file is created with the user's user-id and group-id but these are subsequently ignored. The mode of the file is created as 0777.
CAUTION: No checking is done when a symbolic link is created. There is nothing to stop a user from creating a symbolic link that refers to itself or to an ancestor of itself or several links that loop around among themselves. Therefore, when evaluating a pathname, it is important to put a limit on the number of symbolic links that may be encountered in case the evaluation encounters a loop. The variable MAXSYMLINKS is used to force the error ELOOP after MAXSYMLINKS symbolic links have been encountered. The value of MAXSYMLINKS should be at least 20.
To create a symbolic link, the ln command is used with the -s option (see [URL="http://uw714doc.sco.com/en/man/html.1/ln.1.html"]ln(1)[/URL]). If the -s option is not used and a user tries to create a link to a file on another file system, a symbolic link will not be created and the command will fail.
The syntax for creating symbolic links is as follows:
ln -s sourcefile1 [ sourcefile2 ... ] target With two arguments:
[LIST]
[*] sourcefile1 may be any pathname and need not exist.
[*] target may be an existing directory or a non-existent file.
[*] If target is an existing directory, a file is created in directory target whose name is the last component of sourcefile1 (`basename sourcefile1`). This file is a symbolic link that references sourcefile1.
[*] If target does not exist, a file with name target is created and it is a symbolic link that references sourcefile1.
[*] If target already exists and is not a directory, an error is returned.
[*] sourcefile1 and target may reside on different file systems.
[/LIST]
With more than two arguments:
[LIST]
[*] For each sourcefile, a file is created in target whose name is sourcefile or its last component (`basename sourcefile`) and is a symbolic link to sourcefile.
[*] If target is not an existing directory, an error is returned.
[*] Each sourcefile and target may reside on different file systems.
[/LIST]
[B]Examples[/B]
The following examples show how symbolic links may be created.
ln -s /usr/src/uts/sys /usr/include/sys In this example /usr/include is an existing directory. But file sys does not exist so it will be created as a symbolic link that refers to /usr/src/uts/sys. The result is that when file /usr/include/sys/x is accessed, the file /usr/src/uts/sys/x will actually be accessed. This kind of symbolic link may be used when files exist in the directory /usr/src/uts/sys but programs often refer to files in /usr/include/sys. Rather than creating corresponding files in /usr/include/sys that are hard links to files in /usr/src/uts/sys, one symbolic link can be used to link the two directories. In this example /usr/include/sys becomes a symbolic link that links the former /usr/include/sys directory to the /usr/src/uts/sys directory.
ln -s /etc/group . In this example the target is a directory (the current directory), so a file called group (`basename /etc/group`) is created in the current directory that is a symbolic link to /etc/group. ln -s /fs1/jan/abc /var/spool/abc In this example we imagine that /fs1/jan/abc does not exist at the time the command is issued. Nevertheless, the file /var/spool/abc is created as a symbolic link to /fs1/jan/abc. Later, /fs1/jan/abc may be created as a directory, regular file, or any other file type. The following example illustrates the use of more than two arguments:
ln -s /etc/group /etc/passwd . The user would like to have the group and passwd files in the current directory but cannot use hard links because /etc is a different file system. When more than two arguments are used, the last argument must be a directory; here it is the current directory. Two files, group and passwd, are created in the current directory, each a symbolic link to the associated file in /etc. [B]Removing symbolic links[/B]
Normally, when accessing a symbolic link, one follows the link and actually accesses the referenced file. However, this is not the case when one attempts to remove a symbolic link. When the [URL="http://uw714doc.sco.com/en/man/html.1/rm.1.html"]rm(1)[/URL] command is executed and the argument is a symbolic link, it is the symbolic link that is removed; the referenced file is not touched.
[B]Accessing symbolic links[/B]
Suppose abc is a symbolic link to file def. When a user accesses the symbolic link abc, it is the file permissions (ownership and access) of file def that are actually used; the permissions of abc are always ignored. If file def is not accessible (that is, either it does not exist or it exists but is not accessible to the user because of access permissions) and a user tries to access the symbolic link abc, the error message will refer to abc, not file def.
[B]Copying symbolic links[/B]
This section describes the behavior of the [URL="http://uw714doc.sco.com/en/man/html.1/cp.1.html"]cp(1)[/URL] command when one or more arguments are symbolic links. With the [URL="http://uw714doc.sco.com/en/man/html.1/cp.1.html"]cp(1)[/URL] command, if any argument is a symbolic link, that link is followed. Suppose the command line is
cp sym file3 where sym is a symbolic link that references a regular file test1 and file3 is a regular file. After execution of the command, file3 gets overwritten with the contents of the file test1. If the last argument is a symbolic link that references a directory, then files are copied to that directory. Suppose the command line is
cp file1 sym symd where file1 is a regular file, sym is a symbolic link that references a regular file test1, and symd is a symbolic link that references a directory DIR. After execution of the command, there will be two new files, DIR/file1 and DIR/sym that have the same contents as file1 and test1.
[B]Linking symbolic links[/B]
This section describes the behavior of the [URL="http://uw714doc.sco.com/en/man/html.1/ln.1.html"]ln(1)[/URL] command when one or more arguments are symbolic links. To understand the difference in behavior between this and the [URL="http://uw714doc.sco.com/en/man/html.1/cp.1.html"]cp(1)[/URL] command, it is useful to think of a copy operation as dealing with the contents of a file while the link operation deals with the name of a file.
Let us look at the case where the source argument to ln is a symbolic link. If the -s option is specified to ln, the command calls the symlink system call (see [URL="http://uw714doc.sco.com/en/man/html.2/symlink.2.html"]symlink(2)[/URL]). symlink does not follow the symbolic link specified by the source argument and creates a symbolic link to it. If -s is not specified, ln invokes the [URL="http://uw714doc.sco.com/en/man/html.2/link.2.html"]link(2)[/URL] system call. link follows the symbolic link specified by the source argument and creates a hard link to the file referenced by the symbolic link.
For the target argument, ln invokes a stat system call (see [URL="http://uw714doc.sco.com/en/man/html.2/stat.2.html"]stat(2)[/URL]). If stat indicates that the target argument is a directory, the files are linked in that directory. Otherwise, if the target argument is an existing file, it is overwritten. This means that if the second argument is a symbolic link to a directory, it is followed, but if it is a symbolic link to a regular file, the symbolic link is overwritten.
For example, if the command line is
ln sym file1 where sym is a symbolic link that references a regular file foo, and file1 is a regular file, file1 is overwritten and hard-linked to foo. Thus a hard link to a regular file has been created.
If the command is
ln -s sym file1 where the files are the same as in first example, file1 is overwritten and becomes a symbolic link to sym. If the command is
ln file1 sym where the files are the same as in the first example, sym is overwritten and hard-linked to file1. When the last argument is a directory as in
ln file1 sym symd where symd is a symbolic link to a directory DIR, and file1 and sym are the same as in the first example, the file DIR/file1 is hard-linked to file1 and DIR/sym is hard-linked to foo. [B]Moving symbolic links[/B]
This section describes the behavior of the [URL="http://uw714doc.sco.com/en/man/html.1/mv.1.html"]mv(1)[/URL] command. Like the [URL="http://uw714doc.sco.com/en/man/html.1/ln.1.html"]ln(1)[/URL] command, [URL="http://uw714doc.sco.com/en/man/html.1/mv.1.html"]mv(1)[/URL] deals with file names rather than file contents. With two arguments, a user invokes the [URL="http://uw714doc.sco.com/en/man/html.1/mv.1.html"]mv(1)[/URL] command to rename a file. Therefore, one would not want to follow the first argument if it is a symbolic link because it is the name of the file that is to be changed rather than the file contents. Suppose that sym is a symbolic link to /etc/passwd and abc is a regular file. If the command
mv sym abc is executed, the file sym is renamed abc and is still a symbolic link to /etc/passwd. If abc existed (as a regular file or a symbolic link to a regular file) before the command was executed, it is overwritten. Suppose the command is
mv sym1 file1 symd where sym1 is a symbolic link to a regular file foo, file1 is a regular file, and symd is a symbolic link that references a directory DIR. When the command is executed, the files sym1 and file1 are moved from the current directory to the DIR directory so that there are two new files, DIR/sym1, which is still a symbolic link to foo, and DIR/file1. In UnixWare, the [URL="http://uw714doc.sco.com/en/man/html.1/mv.1.html"]mv(1)[/URL] command uses the [URL="http://uw714doc.sco.com/en/man/html.2/rename.2.html"]rename(2)[/URL] system call. If the first argument to [URL="http://uw714doc.sco.com/en/man/html.2/rename.2.html"]rename(2)[/URL] is a symbolic link, [URL="http://uw714doc.sco.com/en/man/html.2/rename.2.html"]rename(2)[/URL] does not follow it; instead it renames the symbolic link itself. In System V prior to Release 4, a file was moved using the [URL="http://uw714doc.sco.com/en/man/html.2/link.2.html"]link(2)[/URL] system call followed by the [URL="http://uw714doc.sco.com/en/man/html.2/unlink.2.html"]unlink(2)[/URL] system call. Since [URL="http://uw714doc.sco.com/en/man/html.2/link.2.html"]link(2)[/URL] and [URL="http://uw714doc.sco.com/en/man/html.2/unlink.2.html"]unlink(2)[/URL] do not follow symbolic links, the result of those two operations is the same as the result of a call to [URL="http://uw714doc.sco.com/en/man/html.2/rename.2.html"]rename(2)[/URL].
Thanks for adding the tut. Will be reading and will definitely try it out.
Thanks again!
Sent from my HTC Desire using XDA App
Thanks a lot for the tutorial. Basic stuff nicly explained. i tried the push method via adb to push a font into system/fonts directory still it says read only permission
C:\Users\Mayu>adb shell
# mount
mount
rootfs / rootfs ro 0 0
tmpfs /dev tmpfs rw,mode=755 0 0
devpts /dev/pts devpts rw,mode=600 0 0
proc /proc proc rw 0 0
sysfs /sys sysfs rw 0 0
none /acct cgroup rw,cpuacct 0 0
tmpfs /mnt/asec tmpfs rw,mode=755,gid=1000 0 0
tmpfs /mnt/obb tmpfs rw,mode=755,gid=1000 0 0
none /dev/cpuctl cgroup rw,cpu 0 0
/dev/block/mtdblock0 /system yaffs2 rw 0 0
/dev/block/mtdblock1 /data yaffs2 rw,nosuid,nodev 0 0
/dev/block/mtdblock2 /cache yaffs2 rw,nosuid,nodev 0 0
/dev/block/vold/179:0 /mnt/sdcard vfat rw,dirsync,nosuid,nodev,n
id=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp437,io
1,shortname=mixed,utf8,errors=remount-ro 0 0
/dev/block/vold/179:0 /mnt/secure/asec vfat rw,dirsync,nosuid,no
000,gid=1015,fmask=0702,dmask=0702,allow_utime=0020,codepage=cp4
8859-1,shortname=mixed,utf8,errors=remount-ro 0 0
tmpfs /mnt/sdcard/.android_secure tmpfs ro,size=0k,mode=000 0 0
Click to expand...
Click to collapse
error mesg
C:\Users\Mayu>adb push E:\soft\Android\Indic\DroidSansFallback.ttf \system\fonts
failed to copy 'E:\soft\Android\Indic\DroidSansFallback.ttf' to '\system\fonts':
Read-only file system
Click to expand...
Click to collapse
PS: pull works like charm. please guide me if u hav time. Thanks.
DroidMayu said:
Thanks a lot for the tutorial. Basic stuff nicly explained. i tried the push method via adb to push a font into system/fonts directory still it says read only permission
error mesg
PS: pull works like charm. please guide me if u hav time. Thanks.
Click to expand...
Click to collapse
Yup, on an s on system, even though system can be mounted as rewrite, writing isn't allowed. You have to execute the commands in recovery mode
Sent from my HTC Desire using XDA App
Great tutorial! Thanks for that, definitely noob friendly...
Have a question about the following,
DATAOPTS:
(no option) - don't touch the data partition
-w - wipe the data partition
-d - flash the data partition
I have the Samsung Galaxy S I9000 (not sure if that makes a difference) and if my screen breaks or i have some sort of hardware problem. After flashing the stock rom back on do i use the above commands to wipe the evidence of any programs that suggest the device was previously rooted. If so which one wipe or flash?
Thanks
Thank You!!!
Hey Droidzone,
I'm really in awe of you, and need to thank you for the amazing work you're doing here - at XDA.
I just can't find the thank you button on the forums.(I could be blind !!!)
Thanks a zillion!!!
Hi,
on my Galaxy Nexus don't works the mount /sdcard from recovery by ADB.
adb shell
~ # mount /sdcard/
mount: can't find /sdcard/ in /etc/fstab
~ #
if type mount, the result below:
rootfs on / type rootfs (rw)
tmpfs on /dev type tmpfs (rw,nosuid,relatime,mode=755)
devpts on /dev/pts type devpts (rw,relatime,mode=600)
proc on /proc type proc (rw,relatime)
sysfs on /sys type sysfs (rw,relatime)
/dev/block/platform/omap/omap_hsmmc.0/by-name/cache on /cache type ext4 (rw,nodev,noatime,nodiratime,barrier=1,data=ordered)
Help me thanks
Wrong subforum. This should be in Q&A section.
ge-Nexus-t mit Tapatalk
You can't mount the SD because it's not UMS.
You can push and pull files in recovery with ADB though.
El Daddy said:
You can't mount the SD because it's not UMS.
You can push and pull files in recovery with ADB though.
Click to expand...
Click to collapse
What's UMS?
pilot-calc22 said:
What's UMS?
Click to expand...
Click to collapse
USB Mass Storage.
How to do for flash recovery .IMG from adb ?
Can I with echo command etc. Etc.
How ?
pilot-calc22 said:
How to do for flash recovery .IMG from adb ?
Can I with echo command etc. Etc.
How ?
Click to expand...
Click to collapse
That's not something you do in recovery. You flash it with fastboot while booted into the bootloader.
The command would be fastboot flash recovery nameofrecovery.img
El Daddy said:
That's not something you do in recovery. You flash it with fastboot while booted into the bootloader.
The command would be fastboot flash recovery nameofrecovery.img
Click to expand...
Click to collapse
If in ADB type "flash_image recovery namerecovery.img "
I've this error: can't find recovery partition
Why ? Thanks
pilot-calc22 said:
If in ADB type "flash_image recovery namerecovery.img "
I've this error: can't find recovery partition
Why ? Thanks
Click to expand...
Click to collapse
You can't use that on the GNex. However, you can do it in an ADB shell with root access:
Assuming recovery.img is stored on /sdcard, the command would be:
dd if=/sdcard/recovery.img of=/dev/block/platform/omap/omap_hsmmc.0/by-name/recovery