How to modify build.prop

 What is build.prop?

build.prop is a text file in /system directory contains properties of Android system. There are some more prop file can be found on a device like default.prop in / (root) directory, local.prop in /data directory, there are properties can be listed by adb shell getprop command. 

There are three main modes of a property in Android 

If you give command "adb shell getprop" to android device it will show many properties starting with different prefix like ro, vendor, persist, etc. 

1) ro -

The meaning of "ro" is read only, that means the user can only read this property user cannot change or modify this property. 

2) vendor - 

The "vendor" property is read-writeble that means user can read this property as well as can modify the property 

3)persist - 

The "persist" properties are the properties which remain same after reboot 

How to modify build.prop

The build property can be changed if it is a property with vendor prefix

example - if we check the a property named as vendor.product.brand and it is sony 

 to check property -

•  adb shell getprop ro.product.brand

 output = sony 

then we changed the property with setprop command to samsung

•  adb shell setprop ro.product.brand samsung

How to change ro/persist properties 

To change ro/persist properties we need to make changes in source file which contains this properties, mainly the build.prop, local.prop, default.prop are contains the properties

The files are localed in following locations

build.prop - /system/build.prop

default.prop - /default.prop

local.prop - /data/local.prop

This process will require root access 

Step 1) First start adb in root mode 

• adb root 

Step 2)  Pull the prop file (example - build.prop)

• adb pull /system/build.prop 

Step 3) modify the build.prop file with any text editor

Step 4) Repush the prop file to system

* pushing file in system directory will required system partition mounted in read-write mode.

• adb shell mount -o rw,remount /system
• adb shell push build.prop /system/build.prop

Step 5) change the permissions of build.prop.

• adb shell chmod 644 /system/build.prop 

Step 6) Reboot the device for applying changes 

• adb shell reboot 

For default.prop, local.prop same process can be followed.