Update D-Bus.md [skip ci]

Author: mikebrady

documents/D-Bus.md

@@ -8,11 +8,11 @@ $ shairport-sync -V
 5.0.0-1-gc956d763-AirPlay2-smi10-OpenSSL-Avahi-ALSA-soxr-metadata-dbus-sysconfdir:/etc
 
 ```
-Once Shairport Sync has been built with the D-Bus interface, it must then be installed correctly to provide a Shairport Sync service, on either the D-Bus system bus or the D Bus session bus.
-To become available as a system-wide service on the D-Bus system bus, it must be installed as a system service using the `# make install` step of the build process. This installs the appropriate service files and sets required permissions.
+Once Shairport Sync has been built with the D-Bus interface, it must then be installed correctly to provide a Shairport Sync service either on the D-Bus `system` bus or the D Bus `session` bus.
+To become available as a system-wide service on the D-Bus `system` bus, it must be installed as a system service using the `# make install` step of the build process. This installs the appropriate service files and sets required permissions.
 Remember to enable Shairport Sync to start as a system service. You may also need to restart the entire system to allow the service to be seen.
 
-If Shairport Sync is installed as a user service, it will not be able to become a service on the D-Bus system bus, but it can be added to the D-Bus session bus. Edit the configuration file to select the session bus, or add the option `--dbus_default_message_bus=session` to the command line.
+If Shairport Sync is installed as a user service, it will not be able to become a service on the D-Bus `system` bus, but it can be added to the D-Bus `session` bus. Edit the configuration file to select the `session` bus, or add the option `--dbus_default_message_bus=session` to the command line.
 
 ### D-Feet
 On desktop Linuxes with a GUI, e.g. Ubuntu, D-Feet is a great tool for examining a D-Bus service:
@@ -27,118 +27,118 @@ After attempting to send some commands, it will listen for property changes on t
 
 ### Command Line Examples
 
-The examples below are based on Shairport Sync running as a system service and use the standard CLI tool `dbus-send`:
+The examples below are based on Shairport Sync running as a `system` service and use the standard CLI tool `dbus-send`:
 * Get `Active` Status -- `true` when Shairport Sync is playing (and for a short time later); `false` otherwise.
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:Active
+   $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:Active
 ```
 * Get Log Verbosity
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:Verbosity
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:Verbosity
 ```
 * Return Log Verbosity
 ```
-  echo `dbus-send --print-reply=literal --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:Verbosity`
+  $ echo `dbus-send --print-reply=literal --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:Verbosity`
 ```
 * Set Log Verbosity to 2
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync.Diagnostics string:Verbosity variant:int32:2
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync.Diagnostics string:Verbosity variant:int32:2
 ```
 * Get Statistics-Requested Status
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:Statistics
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:Statistics
 ```
 * Set Statistics-Requested Status to `true`
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync.Diagnostics string:Statistics variant:boolean:true
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync.Diagnostics string:Statistics variant:boolean:true
 ```
 * Are File Name and Line Number included in Log Entries?
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:FileAndLine
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:FileAndLine
 ```
 * Include File Name and Line Number in Log Entries
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync.Diagnostics string:FileAndLine variant:boolean:true
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync.Diagnostics string:FileAndLine variant:boolean:true
 ```
 * Is Elapsed Time included in Log Entries?
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:ElapsedTime
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.Diagnostics string:ElapsedTime
 ```
 * Include Elapsed Time in Log Entries
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync.Diagnostics string:ElapsedTime variant:boolean:true
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync.Diagnostics string:ElapsedTime variant:boolean:true
 ```
 * Get Drift Tolerance
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:DriftTolerance
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:DriftTolerance
 ```
 * Set Drift Tolerance to 1 millisecond
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:DriftTolerance variant:double:0.001
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:DriftTolerance variant:double:0.001
 ```
 * Is Loudness enabled:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:LoudnessEnabled
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:LoudnessEnabled
 ```
 * Enable Loudness Filter
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:LoudnessEnabled variant:boolean:true
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:LoudnessEnabled variant:boolean:true
 ```
 * Get Loudness Threshold
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:LoudnessThreshold
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:LoudnessThreshold
 ```
 * Set Loudness Threshold
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:LoudnessThreshold variant:double:-15.0
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:LoudnessThreshold variant:double:-15.0
 ```
 * Is Convolution enabled:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:ConvolutionEnabled
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:ConvolutionEnabled
 ```
 * Enable Convolution
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:ConvolutionEnabled variant:boolean:true
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:ConvolutionEnabled variant:boolean:true
 ```
 * Get Convolution Gain:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:ConvolutionGain
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:ConvolutionGain
 ```
 * Set Convolution Gain -- the gain applied after convolution is applied -- to -10.0 dB
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:ConvolutionGain variant:double:-10
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:ConvolutionGain variant:double:-10
 ```
 * Get Convolution Impulse Response Files:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:ConvolutionImpulseResponseFiles
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:ConvolutionImpulseResponseFiles
 ```
 * Set Convolution Impulse Response Files:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:ConvolutionImpulseResponseFiles variant:string:"'/home/pi/filters/Sennheiser HD 205 minimum phase 48000Hz.wav', '/home/pi/filters/Sennheiser HD 205 minimum phase 44100Hz.wav'"
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:ConvolutionImpulseResponseFiles variant:string:"'/home/pi/filters/Sennheiser HD 205 minimum phase 48000Hz.wav', '/home/pi/filters/Sennheiser HD 205 minimum phase 44100Hz.wav'"
 ```
 * Get Convolution Impulse Response File Maximum Length:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:ConvolutionMaximumLengthInSeconds
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:ConvolutionMaximumLengthInSeconds
 ```
 * Set Convolution Impulse Response File Maximum Length:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:ConvolutionMaximumLengthInSeconds variant:double:1
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:ConvolutionMaximumLengthInSeconds variant:double:1
 ```
 * Get the Protocol that Shairport Sync was built for -- AirPlay or AirPlay 2:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:Protocol
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:Protocol
 ```
 * Get the current volume level. This returns a value between -30.0 and 0.0, which is linear on the UI volume control. It can also return -144.0 to indicate mute.
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:Volume
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync string:Volume
 ```
 * Set the current volume level. This should be a value between -30.0 and 0.0. Set a value of -144.0 to mute. Note that all this is done locally on the Shairport Sync device itself. The volume control of audio source (e.g. iTunes / macOS Music / iOS) is not updated to reflect any changes.
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:Volume variant:double:-10.0
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Set string:org.gnome.ShairportSync string:Volume variant:double:-10.0
 ```
 * Drop the current session immediately. Shairport Sync will immediately stop playing and drop the connection from the audio source. This may show up as an error at the source.
 ```
-  dbus-send --system --print-reply --type=method_call --dest=org.gnome.ShairportSync '/org/gnome/ShairportSync' org.gnome.ShairportSync.DropSession
+  $ dbus-send --system --print-reply --type=method_call --dest=org.gnome.ShairportSync '/org/gnome/ShairportSync' org.gnome.ShairportSync.DropSession
 ```
 #### Remote Control
 Remote Control commands are sent as requests to the player (iOS, iTunes, macOS Music, etc.). Different versions of the players implement different subsets of the following commands.
@@ -147,28 +147,28 @@ Remote Control commands are sent as requests to the player (iOS, iTunes, macOS M
 
 * Check if Remote Control is available:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.RemoteControl string:Available
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.RemoteControl string:Available
 ```
 * Send the `play` command to the player:
 ```
-  dbus-send --system --print-reply --type=method_call --dest=org.gnome.ShairportSync '/org/gnome/ShairportSync' org.gnome.ShairportSync.RemoteControl.Play
+  $ dbus-send --system --print-reply --type=method_call --dest=org.gnome.ShairportSync '/org/gnome/ShairportSync' org.gnome.ShairportSync.RemoteControl.Play
 ```
   Remote Control commands include: `Play`, `Pause`, `PlayPause`, `Resume`, `Stop`, `Next`, `Previous`, `VolumeUp`, `VolumeDown`, `ToggleMute`, `FastForward`, `Rewind`, `ShuffleSongs`.
 
 * Set Airplay Volume using Remote Control. Airplay Volume is between -30.0 and 0.0 and maps linearly onto the slider, with -30.0 being lowest and 0.0 being highest.
 ```
-  dbus-send --system --print-reply --type=method_call --dest=org.gnome.ShairportSync '/org/gnome/ShairportSync' org.gnome.ShairportSync.RemoteControl.SetAirplayVolume double:-10.0
+  $ dbus-send --system --print-reply --type=method_call --dest=org.gnome.ShairportSync '/org/gnome/ShairportSync' org.gnome.ShairportSync.RemoteControl.SetAirplayVolume double:-10.0
 ```
 #### Advanced Remote Control
 Some commands and properties are accessible only through the `AdvancedRemoteControl` interface.
 
-**Note:** Unfortunately, at this time -- early 2026 -- these requests are ignored, so advance remote control doesn't work.
+**Note:** Unfortunately, at this time -- early 2026 -- these requests are ignored, so advanced remote control doesn't work.
 
 * Check if Advanced Remote Control is available:
 ```
-  dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.AdvancedRemoteControl string:Available
+  $ dbus-send --print-reply --system --dest=org.gnome.ShairportSync /org/gnome/ShairportSync org.freedesktop.DBus.Properties.Get string:org.gnome.ShairportSync.AdvancedRemoteControl string:Available
 ```
 * Set Volume using Advanced Remote Control:
 ```
-  dbus-send --system --print-reply --type=method_call --dest=org.gnome.ShairportSync '/org/gnome/ShairportSync' org.gnome.ShairportSync.AdvancedRemoteControl.SetVolume int32:50
+  $ dbus-send --system --print-reply --type=method_call --dest=org.gnome.ShairportSync '/org/gnome/ShairportSync' org.gnome.ShairportSync.AdvancedRemoteControl.SetVolume int32:50
 ```