Easiest How to use ADB, Logcat, etc for Noobs and Newbies


ADB :

Android Debug Bridge
Very useful program made itself by Google for Programmers and developers. Its based on command line and basically communicates with your Android to respond to certain commands. There is vast amount of knowledge about adb but its most useful commands limit to getting:-

Logcat:-
A real time log of what is happening in background of our devices. It is really useful for developers to see which component has malfunctioned and helps to narrow down their search for what failed and what needs to be fixed. Several times users are asked to give logcats of their devices which are giving errors. We will go in detail that how to get logcats in every and easiest way possible.

App Installation and Management:-
adb proves really handy if you want to install apks directly from your PC or want to batch install or delete them.

Shell Execution:-
You must have heard of Terminal Emulator. It is an app for android to execute shell commands(linux commands) which are basically present as applets in /system/bin, /system/sbin or /system/xbin(in our case) folders. A very imporant applet called busybox is installed there mainly used for execution of basic commands during root browsing or ROM installation. Many times updater script of ROMs use busybox commands to install it. Well, these commands can be initiated from your device too but they can be initiated from adb also making it easy for programmers.

Pushing and Pulling:-
Most used commands of adb. adb makes it a piece of cake for new device developers to get an ideo of structure and basic knowledge of devices by pulling command. We can pull out i.e copy any files or folders from our devices to our PC, even the root directories without rooting the devices. It help rooters and ROM chefs of new devices to get an idea and implement their mods on them. Pushing is also very useful command. It copies your files and folders from PC to your device. Very useful in pushing some /system apps and other things

Remounting and Setting Permissions

Basic commands:-
Of-course basic commands such as rebooting and rebooting in recovery mode and download mode are supported.

Others:-
There are several other features of adb such as fastboot, aapt, etc

Setting up ADB

Pre Requirements:-
USB Debugging MUST be turned ON in the device for ADB to see it & Developer options is hidden in Android 4.2 and
above, Hitting Build number 10 times in
About Phone/Tablet reveals the menu (Thanks lilHermit for reminding me to add it)

Assuming you all these ready and working properly, we continue
If you are having trouble completing Pre-Requisites, there are several guides featuring them too

Start :
If zip file, then extract it to C:\android-sdk
If exe file then double click on it and install it in C:\ Drive(or any other drive you want)
  • Now to get adb and other tools, you need to download 'Platform Tools'
To download them, go to the android-sdk folder and double click on SDK Manager
It will ask you which package to download? However, it is your choice which package to Download, but here, we will only talk about platform
Tools. So, simply tick on Platform Tools and click on install. Once you have done it. Go to the platform-tools folder in the directory where you installed android-sdk. You will find several files there like adb, fastboot, aapt, etc
  • Now, you can backup the whole folder of android-sdk to any external storage that will make you not download package
again if you want to. You can have it placed in any computer and run it as it does not require registry to work
  • Now, you are just one step away from using adb. Next step is SKIPPING SETTING ENVIRONMENT VARIABLE (If you however want to set environment variables.
We can easily append the sdk platform-tools and tools folder to your systems environmental path variable directly from command line(cmd) by simply issuing one command and performing a system reboot:
Code:
[COLOR=Black]SETX PATH "%PATH%;[/COLOR][COLOR=Indigo]SDK_Install_Path[/COLOR][COLOR=Black]\platform-tools;[/COLOR][COLOR=Indigo]SDK_Install_Path[/COLOR][COLOR=Black]\android-sdk-windows\tools" -m[/COLOR]
Just replace the "SDK_Install_Path" in the above with the proper path of your SDK installation. Example: C:\android-sdk-windows
(Thanks to WugFresh for telling me :victory:)

Many guides on internet say that it is to be done for making it easy for users and if you have some basic knowledge of Command Prompt,
you will know that to execute any application with command prompt, you first need to change the directory to the one where application is
placed. And to skip changing the directories every time you open CMD, you need to put that application is environment variable. However, we will not do so.
  • Type cmd in the search bar. Copy cmd.exe from there. Go to the directory where you have installed android-sdk. Go to platform-tools folder. Paste cmd there, right click on it and in the settings, select Run as Administrator.
  • You are done. Now what to do in it?

ADB Commands
Type adb in command prompt. And several commands will show up on your screen. It is very difficult to analyse these all commands, so we will only talk about most used and important commands

Connect your device via USB cable
And open the CMD in platform-tools folder(Make a shortcut of it on desktop). And type the suitable commands

Code:
adb devices

Will show the list of devices attached to the PC andtheir serial numbers. If this shows up correctly on your PC, then it means that everything is fine for continuing.

Logcat
Code:
adb logcat

It will display the real time log of your device
Best time to do it is when your device boots up
Now, many users ask me how to copy the logcat and upload it from CMD

There are several methods:-
  • Right click on the Title Bar of Command Prompt. Hover the cursor over edit and select mark. Select all the things you want to copy and then click enter. All the things will be copied to clipboard.
  • This is the correct way of getting logcat saved.
Code:
adb logcat > logcat.txt
This command will create a logcat.txt document in platform-tools folder with the complete logcat of the device. Ofcourse you can type any name instead of logcat.txt
  • I prefer taking logcat this way as it neatly compiles logs of different time
Code:
adb logcat -v long > logcat.txt
This is a very nice way to get logcat.

Installing Apps
Code
adb install %PATH OF APK%

This will install an app on your Android
For example, if my app AreeB.apk is in G:\ drive (G:\AreeB.apk)
Then I will type
Code:
adb install G:\AreeB.apk

Be sure your apk is not in a folder that has space in its name, else the command will break at space bar.
For eg:-

G:\Program Files\AreeB.apk

Note:
If you have spaces in path of apk, you can execute the command without breakage if you include the path inside quotes. (Thanks to etcman)
Eg:-
Code:
adb install "G:\Program Files\AreeB.apk"

Mounting
However, I never found any problem in tweaking with system files with adb, but some users said that they couldn't do it, so the problem was that their system partition was mounted as Read Only(R/O)
So, it is necessary now to tell how to mount system partition as Read Write(R/W)
Code:
adb remount

It is easiest way to do so, if it does not work then
There is another method that we will discuss in ADB Shell commands section

Pushing and Pulling

For pushing,
Type
Code:
adb push %PATH TO BE PUSHED% %PATH WHERE TO BE PUSHED%

Suppose I have an app named SystemUI.apk(PATH = G:\SystemUI.apk) which I want to push in /system/app/ on my android(or in other words, install an app as a system app). Then I would type
Code:
adb push G:\SystemUI.apk /system/app/

More examples
G:\Dance.txt file to be pushed in Dance folder in sdcard
Code:
adb push G:\Dance.txt /sdcard/Dance/

OR
Code:
adb push G:\Dance.txt /mnt/sdcard/Dance/

G:\Movies folder to be transferred in SDCARD in Videos Folder
Code:
adb push G:\Movies /sdcard/Videos/

G:\system\framework\framework-res.apk to be pushed in /system/framework/
Code:
adb push G:\system\framework\framework-res.apk /system/framework/

For pulling,
push command replaces with pull and paths are swapped
Code:
adb pull %PATH TO BE PULLED FROM% %PATH TO PLACE PULLED FILE%

Example,
All system apps are to be pulled to G:\ROM\system\app
Code:
adb pull /system/app G:\ROM\system\app\

build.prop to be extracted to desktop
Code:
adb pull /system/build.prop C:\Users\Areeb\Desktop\

However, if a folder is in platform-tools folder, you don't need to type full path
Suppose if I type
Code:
adb pull /system/ system

Then a folder named system will be created inside platform-tools with all the files in system in it
If a file is in platform-tools folder, then also no need to type full path

For example,
There is an app name DeskClock.apk in this folder then, to push it to /system/app, type
Code:
adb push DeskClock.apk /system/app/

ADB Shell Commands
This mode of adb allows you to execute linux shell commands from your PC
These commands can aldo be executed through the mobile using Terminal Emulator

To initiate shell mode
Type
Code:
adb shell

You will get an prompt like this
sh-3.2#

Now you are in shell mode
adb commands won't work here and a new set of commands will work here. But we will only go in a little detail here.
Assuming you are in adb shell mode, I will only type commands that will work on shell. Note:- These commands won't work if you type them alone on cmd. But, these command will directly work on your mobile's Terminal Emulator
As these commands can also work on mobile, I am going to tell you a way of taking logcat on mobile
Type
Code:
logcat

You will see log of your device
To save this
Type
Code:
logcat > /sdcard/log.txt

A file named log.txt will be generated in sdcard

Uninstalling Applications

Code:
cd /data/app

This will change the directory to /data/app
Code:
ls

This will show the list of files in there
Suppose, there is an app named com.opera.browser (Opera Mobile) you want to uninstall it
Type
Code:
rm -r com.opera.browser

This will uninstall the app

Mounting Command:-

Code:
mount -o rw,remount /dev/block/mtdblock3 /system

Miscellanous commands:-
  • su : Initiates root request
  • du : Shows file foldrs and size
  • date: Shows todays date
  • ls : Shows list of directory
  • cd : Changes working directory
  • rm : Removes the file
  • logcat : Displays logcat
  • mount : Mounts the partition
  • busybox : Busybox Applets

Credits
  • Google: For Android and several searchings
  • Samsung: For Galaxy Ace s5830I
  • paxChristos for amazing logcat guide
  • Broadcom: For their Open Sourceness
  • XDA Forums : For the precious knowledge

source