I cannot find a reference to the "build.prop" file in the Android documentation but google answers at the question ' what is "build.prop"':

    The “build.prop” file is a system file that exists on every Android device. The file contains build information and other system properties which are used throughout the operating system.

and stackoverflow is thriving with questions on how to edit this file.

The file contains part of the information returned by the getprop command and all the information we are needing here.

Here is its content and access rights on an android-24-x86_64 emulator:

generic_x86_64:/data/local/tmp/python $ ls -al /system/build.prop
-rw-r--r-- 1 root root 2083 2017-07-12 22:01 /system/build.prop
generic_x86_64:/data/local/tmp/python $ cat /system/build.prop

# begin build properties
# autogenerated by buildinfo.sh
ro.build.id=NYC
ro.build.display.id=sdk_phone_x86_64-userdebug 7.0 NYC 4174735 test-keys
ro.build.version.incremental=4174735
ro.build.version.sdk=24
ro.build.version.preview_sdk=0
ro.build.version.codename=REL
ro.build.version.all_codenames=REL
ro.build.version.release=7.0
ro.build.version.security_patch=2017-06-05
ro.build.version.base_os=
ro.build.date=Wed Jul 12 19:46:52 UTC 2017
ro.build.date.utc=1499888812
ro.build.type=userdebug
ro.build.user=android-build
ro.build.host=wphl5.hot.corp.google.com
ro.build.tags=test-keys
ro.build.flavor=sdk_phone_x86_64-userdebug
ro.product.model=Android SDK built for x86_64
ro.product.brand=Android
ro.product.name=sdk_phone_x86_64
ro.product.device=generic_x86_64
ro.product.board=
# ro.product.cpu.abi and ro.product.cpu.abi2 are obsolete,
# use ro.product.cpu.abilist instead.
ro.product.cpu.abi=x86_64
ro.product.cpu.abilist=x86_64,x86
ro.product.cpu.abilist32=x86
ro.product.cpu.abilist64=x86_64
ro.product.manufacturer=unknown
ro.product.locale=en-US
ro.wifi.channels=
ro.board.platform=
# ro.build.product is obsolete; use ro.product.device
ro.build.product=generic_x86_64
ro.product.cpu.abilist=x86_64,x86
ro.product.cpu.abilist32=x86
ro.product.cpu.abilist64=x86_64
ro.product.manufacturer=unknown
ro.product.locale=en-US
ro.wifi.channels=
ro.board.platform=
# ro.build.product is obsolete; use ro.product.device
ro.build.product=generic_x86_64
# Do not try to parse description, fingerprint, or thumbprint
ro.build.description=sdk_phone_x86_64-userdebug 7.0 NYC 4174735 test-keys
ro.build.fingerprint=Android/sdk_phone_x86_64/generic_x86_64:7.0/NYC/4174735:userdebug/test-keys
ro.build.characteristics=emulator
# end build properties
#
# from build/target/board/generic_x86_64/system.prop
#
#
# system.prop for generic sdk
#

rild.libpath=/system/lib/libreference-ril.so
rild.libargs=-d /dev/ttyS0

#
# ADDITIONAL_BUILD_PROPERTIES
#
ro.config.notification_sound=OnTheHunt.ogg
ro.config.alarm_alert=Alarm_Classic.ogg
persist.sys.dalvik.vm.lib.2=libart.so
dalvik.vm.isa.x86_64.variant=x86_64
dalvik.vm.isa.x86_64.features=default
dalvik.vm.isa.x86.variant=x86
dalvik.vm.isa.x86.features=default
dalvik.vm.lockprof.threshold=500
xmpp.auto-presence=true
ro.config.nocheckin=yes
net.bt.name=Android
dalvik.vm.stack-trace-file=/data/anr/traces.txt