adb shell modify build.prop

Modify build.prop as an example: (follow the gourd, pay attention to the path. Each line of command is one step.)
    a) adb shell
    b) su
(**a, b these two steps are to obtain root privileges, please pay attention to the phone display , if there is a pop-up window, please click OK**)
    c) mount -o rw,remount /system
(**c this step is to mount the system for read and write**)
    d) cp /system/build.prop /system/ build.prop.bak
(**d This step is to backup build.prop to build.prop.bak, if you don’t want to backup, you can skip this step.**)
    e) cp /sdcard/build.prop /system/build.prop
(**e step is to copy and replace the modified source file**)
    e1) mv /sdcard/build.prop /system/build.prop
(**e1 step indicates that some source files will be copied if they exist The replacement failed, so just move and replace it**)
    f) chmod 644 /system/build.prop
(**f this step is to modify the permission to rw-rr**)
    g) reboot
(**restart**)