dumpsys media.audio_flinger这个命令，在做录音相关需求时可能遇到。
身为一名开发者，怎么知道有这个命令了？
看看官方文档怎么说？https://developer.android.google.cn/studio/command-line/
如下图：
输入adb shell dumpsys -l试试看，截图如下：
完整输出内容如下：
MacdeMacBook-Pro:~ mac$ adb shell dumpsys -l
Currently running services:
DockObserver
SurfaceFlinger
accessibility
account
activity
alarm
android.security.keystore
android.service.gatekeeper.IGateKeeperService
appops
appwidget
assetatlas
audio
backup
battery
batteryproperties
batterystats
bluetooth_manager
clipboard
commontime_management
connectivity
consumer_ir
content
country_detector
cpuinfo
dbinfo
device_policy
deviceidle
devicestoragemonitor
diskstats
display
dreams
drm.drmManager
dropbox
fingerprint
gfxinfo
graphicsstats
imms
input
input_method
jobscheduler
launcherapps
location
lock_settings
media.audio_flinger
media.audio_policy
media.camera
media.camera.proxy
media.player
media.radio
media.resource_manager
media.sound_trigger_hw
media_projection
media_router
media_session
meminfo
mount
nemu_service
netpolicy
netstats
network_management
network_score
notification
package
permission
power
print
processinfo
procstats
restrictions
rttmanager
samplingprofiler
scheduling_policy
search
sensorservice
serial
servicediscovery
statusbar
tab
telecom
telephony.registry
textservices
trust
uimode
updatelock
usagestats
usb
user
vibrator
voiceinteraction
wallpaper
webviewupdate
wifi
wifip2p
wifiscanner
window
在最后一行，我们看到熟悉的window，试试先输入adb shell，再输入dumpsys window | grep mCurrentFocus，看看结果，如下图，我们熟悉的Launcher。
这些命令对应的文件存放在哪里？
设备的Android 系统目录/system/bin目录下面，如下图：
