Support for OpenGL ES 3. which performed reboot as expected. Here's how you do it: $ adb shell stop $ adb shell setprop log. adb. In the Monitoring section, select Profile GPU Rendering or Profile HWUI rendering, depending on the version of Android running on the device. dec. To trigger a mid-level SystemUI crash loop, run: adb shell setprop debug. Make a BufferedReader which gets the value (String) by retrieving the data from a inputStreamReader(). adb shell setprop debug. dns1 # if i follow above steps it is not setting system property. phone. lcd_density 240 adb shell wm 使用Device owner管理你的安卓设备。Manage your device with Device owner privilege - BinTianqi/OwnDroid May 21, 2024 · Logging in Android is complex due to the mix of standards used that are combined in logcat. properties or logback. ls -l Dec 8, 2020 · Activation VoLTE without ROOT on android 11: 1. And sorry, I cannot give any advice towards IMEI, never played with that (no need). All of these are line-oriented, consisting of tokens separated by whitespace. The ‘getprop‘ and ‘setprop‘ commands can be used to view and set or change the configuration of the ‘build. app PACKAGE_NAME. For example, from here we know, that getprop / setprop are just API to read and write some database, stored in files on filesystem. setProperty("debug. This documentation describes how to enable this feature on Android N or later versions of the Android OS. Android は、一般的なシステム ロギングに liblog ライブラリを使用しています。 liblog は、次のマクロ形式を使用してサブログ グループのラッパーを提供します。 Nov 9, 2019 · The only step is to delete the module or init. (It does break JUnit though, as mentioned here, so it's not without effect. so file during application launch. Aug 31, 2019 · I tried setprop and it showed that it can't set that property. force_gpu_vsync 1. $ adb shell getprop ro. test に ABC をセット） $ adb root $ adb shell setprop tmp. hdmirotation portrait adb shell setprop persist. Web Apr 9, 2010 · su setprop service. ) For reference, here's my code: When the system is initialised, Android will allocate a shared memory area to store the properties. LENGTH_LONG). OPTIONS property Name of the property to be set value Value of the property (string, numbers, etc) AUTHOR setprop is originally available in the Android AOSP Jan 9, 2014 · 3. To enable Analytics debug mode on an Android device, execute the following commands: adb shell setprop debug. prop files without success. Though it requires adb root, one method to do this would be to use bootctl if available. Share. prop’ file on Android devices. See the examples below: Type ‘adb shell‘ in the cmd window, hit the Enter key and then issue the following command: getprop Mar 16, 2022 · I've got an Android TV Box (orbsmart S86) running on Android 9. It assigns a tag to a memory location, which then can be associated with System properties are key-value pairs that are used to configure various aspects of the Android system. adb. Install the AsusVoLTE app from above, make sure to upgrade if you already have it installed. Change profile QPST PDC 5. 2. This API manages by system process called "property_service". setprop service. prop. 3)ADB debug enabled in phone. Dec 21, 2017 · But when I set the value to adb shell setprop sys. sf. test ABC 全ての値を確認 $ adb shell getprop \[DEVICE_PROVISIONED]: … Oct 19, 2021 · To answer the initial question, let's see, what exeactly getprop / setprop do on Android. Finally, you can use adb commands (launch activity) to Jan 8, 2021 · I did find though that should one turn off the usb with the enable file, issue command setprop persist. I built the native library using Android Studio (creating a native project and then extracting the . My solution survives reboot and OTG would work even when decryption password is not supplied. Here’s the basic syntax: $ adb shell setprop <property_key> <property_value> Replace <property_key> with the name of the property you want to set and <property_value> with the desired value. Running adb shell to an emulator, trying to use setProp for readonly properties, eg setprop ro. For your specific command this would look like. Enable USB Debugging on your phone from Developer Options. enable 1. ) The documentation for malloc debug on older versions of Android Feb 11, 2016 · So the setprop is obviously to those who have access to the platform keys. When using WiFi, I can go to the WiFi-settings and configure the settings there. Oct 30, 2012 · setprop log. If your device does not accept Apr 29, 2024 · OpenGL is a cross-platform graphics API that specifies a standard software interface for 3D graphics processing hardware. app com. The /data/misc/logd/ directory is filled with 256 MB log files. Approximate equivalents across the standards are as follows: setprop service. domain "". Now that your device is booted to FTM Mode, execute the below command to open the Shell environment: adb shell; After that, copy-paste the below command and hit Enter: setprop sys. systemui. prop file from the device: adb pull /system/build. powerctl property. enable 1 setprop persist. config diag,adb Done. If you are running a version of Android older than P, you can still capture a trace with Perfetto using the record_android_trace script. multisim. # 「デモモードを有効にする」ON adb shell settings put global sysui_demo_allowed 1 # systemuiにデモモード開始を通知 adb shell am broadcast -a com. release Jan 6, 2011 · Android Auto General XDA Developers was founded by developers, for developers. UPDATE 1: I guess I can run it from the terminal in Android Studio: I think I could run it even outside of Android Studio, from the terminal. If you don't use ADB often, I would not recommend it, because setting adb causes my S5 to still recognize in device manager, even when it is locked. And this is a nice way to debug an app, so I thought I'd use the same tool to add debug functionality to my app. profile 1. Improve this answer. sys. FA VERBOSE. testing. usb. To trigger a low-level system_server crash loop, run: adb shell setprop debug. getProperties(). config mtp,adb. Next, connect your device to the computer. $ setprop service. mk. But I think this will work until you restart the device. property testing. redirect-stdio true $ adb shell start The system retains this setting until you terminate the emulator/device instance. enable_rescue 1. memcap=8000000ro Apr 29, 2024 · adb shell setprop persist. Jul 2, 2018 · To begin with, download and install ADB and Fastboot drivers onto your system, as shown here. Start by creating your first app. config diag,adb,video [ 500. prop file to your PC in the same directory where your command prompt is running from. hdmirotationlock false adb shell setprop persist. Unless the property name starts with persist. permission. Then use adb connect XXX. In the console, I can do a getprop, setprop. hwrotation 90 to build. redirect-stdio true. When you call just single adb wait-for-device it doesn't guarantee that boot is completed since it only check that daemon Aug 4, 2011 · Brisbane. config diag,adb,video then my device is not listed in adb devices. selinux was abandoned back in Android 6, replacing with kernel cmdline parameter. I tried to set the property from shell: # setprop sys. Reload to refresh your session. (See the “Examples” section. android. But where should I navigate to? Aug 28, 2019 · adb shell su -c 'setprop persist. You can refer to UserManger source code to find how android reads the maximum number of users. Or, if you know, please let me know from where the recovery is pulling data for getprop and if I can change that file. I made an demo program and introduced memory leak in that but the above flag is not able to detect this leak. But I can't remove the key now that it is set (because of May 21, 2024 · This section summarizes useful tools and related commands for debugging, tracing, and profiling native Android platform code when developing platform-level features. This is will be used later on to edit the build. I'm looking for the info regarding sys. tag. Sep 8, 2021 · STEP 5: Fix PDC Android 11 Issue via ADB Commands. Perquisite: 1)Rooted. ) like follows: Code: setprop ro. For example: $ adb shell setprop my. ) Run the following commands in the same build tree. XXX where XXX. This behavior persists until you explicitly disable debug mode by executing the following command: adb shell setprop debug. config diag,diag_mdm,qdss,qdss_mdm,serial_cdev,dpl,rmnet,adb Jan 18, 2022 · I'm trying to use portrait orientation of my Android and display it in full-screen mode on an HDMI monitor. Then in Android Monitor, filter logs for Firebase. config diag,diag_mdm,qdss,qdss_mdm,serial_cdev,dpl,rmnet,adb 4. port 5555 stop adbd start adbd And you can disable it and return ADB to listening on USB with. May 21, 2024 · For information about running Android apps under MTE, see the Developer documentation . CHANGE_CONFIGURATION. For dual sim: su -c setprop persist. Jan 4, 2022 · 1. app . like # setprop net. jpeg. I've used the following setprop commands: setprop persist. Aug 23, 2015 · change settings: setprop with the appropriate values (e. Aug 18, 2010 · Hi all I am trying to set system property so some value. Code: ro. config mtp,ptp,adb allows all USB protocols. List all the To pass an empty value, you need to pass an "empty string" – which is usually specified by two quote marks with nothing between them. crash_system 1. securitycentery. Dec 10, 2019 · The setprop service. 3. You can emulate what apps do with these steps on your device with root and android terminal emulator: $ adbd stop. adb shell 3. Malloc debug is a method of debugging native memory problems. Build AI-powered Android apps with Gemini APIs and more. Thanks. Aug 30, 2019 · To enable analytics debug on android, I have to execute following adb command: adb shell setprop debug. port 5555 stop adbd start adbd Then I can launch adb on my computer, connect to the device and perform various adb commands. build. #> bootctl set-active-boot-slot SLOT. device # raphaelin. It is running as. Aug 12, 2020 · You should call getprop sys. Both crash loops initiate the rescue logic. Jun 7, 2019 · Android's rootfs is a temporary filesystem (not a persistent one like on /system or /data) that gets cleared on every reboot. You switched accounts on another tab or window. enable-vr-mode 1. port 5555 entered at the # prompt of a terminal window on the phone does not complain or throw errors but does not set the service. So in order to get Diag mode up and running, you need to type this command line either on your phone running terminal or on your computer running adb Shell before proceeding to follow the instructions by the OP. 아래에는 사용되는 기본 표준이 자세히 설명되어 있습니다. $ adb shell start. (android) I am writing an app that runs in system/app on an android device. How can I change the default/natural orientation of the device to portrait? Here is what I have tried till now, 1) Added setprop ro. config. Jan 1, 2020 · The AsusLTE app DOESN'T work anymore on Android 11 openbeta. XXX. Hello world. Also make sure your device has Internet access. android:sharedUserId="android. Jul 4, 2023 · adb shell setprop debug. dbg. However, my program cannot create it. app",package Jun 3, 2013 · How do I start an Android app with valgrind? I know I can start an app with the 'am' command, but it starts the app and exits. port property ; setprop persist. Next up, switch off your device and head over to the recovery mode. You need to be root, disable SELinux, and restart the runtime to remove the seccomp filter that will otherwise prevent strace from running: adb root adb shell setenforce 0 adb shell stop adb shell start. what may be May 10, 2022 · Actually android itself reads this property to know if the device supports multi-user or not. adb shell setprop sys. └ Tip: Make a copy of the build. services. Just say i want to change properties of something in the build. The Jan 13, 2015 · su setprop service. renderer skiagl stop start Configure VM acceleration adb shell getprop & adb shell setprop. Using the above commands, you can not only get the properties of your Android’s build. hwc. 로그 표준. OUTPUT The Android Init Language consists of five broad classes of statements: Actions, Commands, Services, Options, and Imports. performance. version $ $ adb shell setprop security. 0 and higher includes support for building the entire Android platform with ASan at once. prop file. Training courses. These are done by the “init” daemon. The only way it worked for me is what I described in my answer. Install an advanced text editor like Notepad++ or Sublime Text on your system. d script which executes setenforce 0 on boot. For example, you can deploy your debuggable app to multiple remote devices without ever needing to physically connect your device via USB. 2) PC with ADB and fastboot. Is it possible to bundle the logging configuration within the application? I'm looking for the equivalent of logging. – Mar 30, 2021 · 3. 107 2. traced. Skia helps the emulator render graphics more smoothly and efficiently. adb shell su -c setprop persist. product. dmesg:- adb shell setprop sys. prop y el valor en ese archivo es raphaelin también. Jul 24, 2013 · Make a process which executes "getprop" from the "/system/bin/getprop" directory and initialize the String which we want to get (ro. Aug 4, 2011. Partial solution: It seems I can turn off with the following command from terminal: stop logd. The c-style backslash escapes may be used to insert whitespace into a token. Double quotes may also be used to prevent whitespace from breaking Apr 7, 2020 · I am trying to use LD_PRELOAD to dynamically load a . He intentado setprop y mostró que no puede establecer esa propiedad. The setprop and getprop commands are used to access the data in that database. For single sim: su -c setprop persist. boot. demo --es command clock --es hhmm 1000 # ネットワーク状態の表示内容を設定 adb shell am I can set a persistent system property on an Android phone (with appropriate permissions) using setprop <key> <value> command: $ adb shell setprop persist. Convert the BufferedReader to String. The main standards used are detailed below: Figure 1: Log level standards. Sep 3, 2012 · 13. FA-SVC VERBOSE adb logcat -v time -s FA FA-SVC Where in Android Studio can I run those commands? Thank you. config "ptp,adb") EDIT: If the above doesn't yield the expected results, it might need root powers. LOCAL_CERTIFICATE := platform. Some of build. 2 with Landscape as the default/natural orientation. OpenGL ES is a subset of the OpenGL specification for embedded devices. product: raphaelin. You have to create an application that changes the device locale. enable 0 works from both Mac and phone shells (confirmed by checking ADB daemon stops and getprop returns 0 for the enable property) En el modo de arranque (es decir, mientras el teléfono está arrancado): # getprop ro. x, and OpenGL ES 2. 136525] android_usb gadget: uvc_function_bind. config dsds. media. Wifi is not used. For my non-rooted device (which I am not allowed to root, so I need to find another way around), if I do adb shell setprop MY_PROP 1 followed by adb shell getprop MY_PROP I get a blank line. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. First thing to do is to set the manifest permission : Finishing : Now that we added the permission we need to create the Simple build and deploy through Android Studio will do. port -1 stop adbd start adbd From a computer, if you have USB access already (no root required) It is even easier to switch to using Wi-Fi, if you already have USB. ravi_arya. config diag,adb" I have tried to enable both using different set of commands like adb shell su -c "setprop sys. Contents of root directory ( / ) are extracted from another partition named boot which contains kernel and ramdisk (though things have changed with system-as-root ). Next, on 4. oem. I added the above code in init. I am wondering, is it posible to enable this from code? I tried: System. <YOUR_LOG_TAG>=<LEVEL> in /data/local. analytics. I know it's silly, but it was my case ;) May 21, 2024 · Android 7. config none. demo --es command enter # 時計の表示内容を設定 adb shell am broadcast -a com. getProperty("TEST")); Toast. Android デバイスでアナリティクスのデバッグモードを有効にするには、次のコマンドを実行します。 adb shell setprop debug. . this, prop, Toast. He comprobado mi build. adb shell setprop persist. boot_completed) ]]; do sleep 1; done; input keyevent 82'. stop adbd. radio. version. 1. logging. debug. 표준 Jul 12, 2023 · To start profiling device GPU rendering while using your app, proceed as follows: On your device, go to Settings and tap Developer Options . I tried some code found here: setprop service. makeText(LoginActivity. config, then turn usb back on the same way, that although it still won't be registered in the settings menu it will cause lsusb to return the correct mode id. Not only that, but then everytime I reboot to TWRP recovery again, I notice that some changes are reversed: getprop と setprop のシェルコマンド. Then start dhcp client. Sep 30, 2020 · 値をセット（tmp. 0. See instructions below in the Recording a trace through the cmdline section. FA VERBOSE adb shell setprop log. You’ve Enabled Or Disabled Diag Mode on Qualcomm device. Note: SLOT is a number, you can find out the labels by looping through them and calling get-suffix for example this little shell script, for slot in $(seq 0 $(expr $(bootctl get-number-slots Jul 27, 2016 · Open a command window on the PC and issue the following command to pull build. At a high level, MTE tags each memory allocation/deallocation with additional metadata. To be Android compatible, devices need to provide drivers for EGL, OpenGL ES 1. demo. Arm v9 introduces Arm Memory Tagging Extension (MTE), a hardware implementation of tagged memory. force-opengl 1. This will enable Firebase debug events for my app, and they will get shown in the Debug View of Firebase console. prop configuration but can also set a value of property tag on the build. To restore original functionality, setprop persist. - then the value gets stored in /data/property folder. I've read that I need to do this: $ adb shell stop. Can I do this on a non-rooted device? Jan 24, 2018 · I am currently trying to get my Android-Phone connected to my Windows machine acting as HID, RNDIS and MASS_STORAGE device simultaneously. crash_sysui 1. It can help detect memory corruption, memory leaks, and use after free issues. custom May 10, 2012 · I can't get my Nexus S (running Android 4. In ADB Commands — Part I i made a small intro to the adb commands. powerctl reboot. Set up a world-writable directory for strace logs, because strace will Apr 16, 2014 · I have my device TI am335xevm running android Jellybean 4. Remember, tweaking these properties can affect system behavior, so proceed with caution. C. singledisplay true adb reboot adb shell wm size 1080x1920 adb shell wm size 1920x1920 The answer was found here, and the relevant documentation was found here. config "mtp,adb" or adb shell setprop sys. Once there, tap on “Mount”. setProperty("TEST", "test"); String prop = (System. port 5555. Jun 4, 2024 · adb shell getprop & adb shell setprop. vndk. If you want to change system properties, adb shell setprop is the command you need. Double quotes may also be used to prevent whitespace from breaking May 29, 2014 · setprop persist. Is there a way to force overriding ro props? android. May 4, 2022 · adb shell su -c "setprop sys. eth0. Example: To change the device’s density: adb shell setprop ro. On Android 10 and below, I've successfully rotated the screen, but what makes me confused is that on Android 11, this method is not working anymore. Or, you can use a helper app, e. malloc 1 adb shell stop adb shell start. So if your device is rooted, you could try to run adb root prior to above commands. HOME_APP_ADJ=1. $ adbd start. Improves audio and video recording quality. quality=100ro. carrier newCarrier, but it won't change it. adb reboot ftm 2. 這樣, 對於測試一些代碼的改動就不是很方便了, 比如我要修改Android 底層C++ 代碼中的 Android. It might be helpful to enable Firebase logs (see this answer ): adb shell setprop log. g. perf_harden 0 C++/Java/Rust에 sysprop을 API로 May 11, 2016 · Below are the Build Prop Tweaks which will help you out to install best function on your devices such as fasten your booting speed increase your internet speed and much more. service. make -j42 SANITIZE_TARGET=address make -j42 Jan 1, 2020 · Step 1 - setting props. The problem is that when I run the command to turn off the second sim card from the console, in the settings there To route the output in this way, you stop a running emulator/device instance and then use the shell command setprop to enable the redirection of output. prop and it did nothing. port 5555 worked on my non-rooted device, now I need to restart adbd as the shell user : $ adb shell shell@android:/ $ getprop ro. The above command will download the build. Each of those Modes as single mode is working fine but I cant get them combined properly, for example, i can use HID, MASS_STORAGE but norfilter filter HID, RNDIS. prop now this would normally be done by setprop But what if i want to disable the phone function i cannot call setprop on a read only property (ro. platform in example). I tried to change the init. Oct 18, 2016 · adb shell root adb shell remount adb shell setprop persist. rc and I replaced it with the original file Aug 29, 2017 · 1. getprop または setprop シェルコマンドを使用することで、プロパティに対して読み取りと書き込みを行えます。詳しくは、getprop --help または setprop --help を呼び出して確認してください。 Jun 28, 2022 · johndaniel. return (*env)->NewStringUTF(env, "Hello from JNI !"); May 21, 2024 · To use strace on an app: Set up the device so that you can run strace. Android Property - setProp配合代碼, 大大加快測試. my. x is optional. However, this doesn't seem to work. 2+ devices, you have to use grant the app CHANGE_CONFIGURATION permission via adb, adb shell pm grant <package_name> android. #> reboot. I found the following command in the Firebase docs: adb shell setprop debug. 前言. It is connected to the LAN and internet via a cable. otg_support true' Some folks on some forums suggested to toggle the value for the global settings key oneplus_otg_auto_disable, but it never worked out for me. Currently I don't need debug log files, so I would like to turn off logging. Open Minimal ADB and Fastboot command prompt on your PC. I have used the this command getprop | grep usb in minicom to check the value of sys. firebase. 자세한 내용을 확인하려면 getprop --help 또는 setprop --help를 호출하세요. enc. app package_name. But when I reboot, I still can't see my device when I run adb devices. property. min_fps (0,60,90,120) (Also note that the last command will set the minimum refresh rate for the entire system but certain apps via Sep 30, 2023 · adb shell setprop. hwui. adb reboot Oct 1, 2014 · 1. getprop 및 setprop 셸 명령어. 그림 1: 로그 수준 표준. Its very easy to use just open up a terminal or command window & add this with your device connected to system. Get started. 2. May 20, 2024 · Android 11 (API level 30) and higher support deploying and debugging your app wirelessly from your workstation using Android Debug Bridge (adb). However, I am finding that I cannot create, write or set a property. You signed out in another tab or window. none. malloc = 1 to find out leak. The following snippet is copied from UserManager source: Apr 14, 2022 · setprop sys. volte_avail_ovr 1. is. so file f Feb 21, 2020 · adb shell setprop log. $ adb shell setprop log. Though each of these standards have similar level construction, they vary in granularity. ADB Command Method (Recommended) Root access is required. answered Dec 28, 2011 at 5:06. show(); The last line displays a good result (I see a Toast with "test") so I know that the property was set properly. The following command, for example, displays the Android system information. function 0. systemui" in Android. I tried to use setprop libc. this. When using images for API level 27 or higher, the emulator can render the Android UI with Skia. En fastboot: > fastboot getvar product. note : install adb if you don't have it installed on system. <YOUR_LOG_TAG> <LEVEL>, or; log. xml, configuration files that are bundled with the application and alter the logging behavior at load-time. dns1 9 # getprop net. enable the ethernet port and then use setprop command to enable dhcp. In this part i will show some more commands available, some off them very useful for debugging situations . Nov 17, 2015 · I tried doing the following: System. この動作は次のコマンドを実行してデバッグモードを明示的に無効にするまで継続します。 May 26, 2024 · Enable Skia rendering for Android UI. in an Android shell and it works great. refresh_rate. prop adb commands, some of them have no real visible effects, but worth the try. 0) to redirect native stdout message to logcat. wlan0. The Android Init Language consists of five broad classes of statements: Actions, Commands, Services, Options, and Imports. Better RAM management. ADB Change Language. To enable Skia rendering, use the following commands in the adb shell: su setprop debug. Aug 6, 2020 · EDIT: I found a command that you can use to change whether the phone is to be multisim or singlesim. Go deeper with our training courses or explore app development on your own. You signed in with another tab or window. 最近, 在Android 開發中遇到一個問題, 有個app 需要每次燒寫 (比如略修改一些代碼, 就要重新編譯, 再燒錄到Android 手機裡)。. test ABC 値を確認 $ adb shell getprop tmp. boot_completed after boot or reboot and together with adb wait-for-device like this: adb wait-for-device shell 'while [[ -z $(getprop sys. Note: The pages in this section and elsewhere within this site recommend the use of adb in conjunction with the setprop argument to debug certain aspects of Android. Run the app and press the Enable VoLTE button; this should set some properties on the device to force-enable VoLTE after we have also done the other steps below. app",package_name) System. start adbd. 이러한 각 표준은 비슷한 수준의 구성을 갖지만, 세분성에서는 다릅니다. From there, you can trigger a system or UI crash loop. 4) patience. setprop sys. config adb will allow adb when developer options are turned on/checked. I have a rooted HTC Hero, and what I want to do is to enable the adbd to listen to a port at boot time. In the Profile GPU Rendering dialog, choose On screen as bars Jun 30, 2019 · 3. # Needed only on Android 9 (P) and 10 (Q) on non-Pixel phones. that's it now you can open up your app & debug view will show your device with all the events etc, after Build AI experiences. tcp. rc file. The “init” daemon will start an android property service. example. config rndis,diag,adb" I've tried via setprop as well as by adding it to one of the *. When I try to access the same property for adb, I get a 1. I can then confirm that the property was set: $ adb shell getprop persist. I tried below commands: adb shell setprop libc. Android에서 로깅은 logcat 에 결합된 표준이 혼합되어 사용되기 때문에 복잡합니다. I couldn't find more info regarding the property: Nov 15, 2020 · Using bootctl. XXX is your ip address found from: $ ifconfig wlan0 | awk '/inet addr/ {print $2}' | cut -d: -f2. So, please advise me on how to set the value using setprop in recovery mode. (If you're building a release higher than Android 9, HWASan is a better choice. #1. getprop 또는 setprop 셸 명령어를 각각 사용하여 속성을 읽거나 쓸 수 있습니다. ro. Now I've configured PIHole on another device and want to tell the android box to use the Pihole as DNS. app. Jun 5, 2024 · Android. board. debuggable 1 setprop persist. prop file before you edit it so that you’ve a Jan 20, 2015 · 1. I'm writing an app that uses the NDK for native C code, and I need to check it for suspected memory errors. uid. Recording a trace setprop - set property via the android property service SYNOPSIS setprop property value DESCRIPTION setprop is an android utility to set up a property via the android property service. setprop dhcp. Run in cmd , each line at a time. igqltambdyxcoztqjhfv