Merge pull request #15926 from fbuihuu/rework-show-status

[thirdparty/systemd.git] / docs / DESKTOP_ENVIRONMENTS.md

diff --git a/docs/DESKTOP_ENVIRONMENTS.md b/docs/DESKTOP_ENVIRONMENTS.md
index 1c8c7aec6e7e905a964523baada86b039161d84c..b0ac5b824d6ccae00d27742fefea6f50165522b5 100644 (file)
--- a/docs/DESKTOP_ENVIRONMENTS.md
+++ b/docs/DESKTOP_ENVIRONMENTS.md
@@ -28,21 +28,21 @@ Currently nothing like this is supported or even planned.
 [`systemd.special(7)`](https://www.freedesktop.org/software/systemd/man/systemd.special.html)
 defines the `graphical-session.target` and `graphical-session-pre.target` to
 allow cross-desktop integration. Furthermore, systemd defines the three base
-slices `background`, `apps` and `session`.
+slices `background`, `app` and `session`.
 All units should be placed into one of these slices depending on their purposes:
 
  * `session.slice`: Contains only processes essential to run the user's graphical session
- * `apps.slice`: Contains all normal applications that the user is running
+ * `app.slice`: Contains all normal applications that the user is running
  * `background.slice`: Useful for low-priority background tasks
 
 The purpose of this grouping is to assign different priorities to the
 applications.
 This could e.g. mean reserving memory to session processes,
 preferentially killing background tasks in out-of-memory situations
-or assinging different memory/CPU/IO priorities to ensure that the session
+or assigning different memory/CPU/IO priorities to ensure that the session
 runs smoothly under load.
 
-TODO: Will there be a default to place units into e.g. `apps.slice` by default
+TODO: Will there be a default to place units into e.g. `app.slice` by default
 rather than the root slice?
 
 ## XDG standardization for applications
@@ -50,25 +50,34 @@ rather than the root slice?
 To ensure cross-desktop compatibility and encourage sharing of good practices,
 desktop environments should adhere to the following conventions:
 
- * Application units should follow the scheme `apps-<launcher>-<ApplicationID>-<RANDOM>.service`,
-   e.g. `apps-gnome-org.gnome.Evince-12345.service`,
-   `apps-flatpak-org.telegram.desktop-12345.service` or `apps-KDE-org.kde.okular-12345.service`.
+ * Application units should follow the scheme `app[-<launcher>]-<ApplicationID>[@<RANDOM>].service`
+ or `app[-<launcher>]-<ApplicationID>-<RANDOM>.scope`
+   e.g:
+    - `app-gnome-org.gnome.Evince@12345.service`
+    - `app-flatpak-org.telegram.desktop@12345.service`
+    - `app-KDE-org.kde.okular@12345.service`
+    - `app-org.kde.amarok.service`
+    - `app-org.gnome.Evince-12345.scope`
  * Using `.service` units instead of `.scope` units, i.e. allowing systemd to
    start the process on behalf of the caller,
    instead of the caller starting the process and letting systemd know about it,
    is encouraged.
+ * The RANDOM should be a string of random characters to ensure that multiple instances
+ of the application can be launched.
+ It can be ommitted in the case of a non-transient application services which can ensure
+ multiple instances are not spawned, such as a DBus activated application.
  * If no application ID is available, the launcher should generate a reasonable
    name when possible (e.g. using `basename(argv[0])`). This name must not
    contain a `-` character.
 
 This has the following advantages:
- * Using the `apps-<launcher>-` prefix means that the unit defaults can be
+ * Using the `app-<launcher>-` prefix means that the unit defaults can be
    adjusted using desktop environment specific drop-in files.
  * The application ID can be retrieved by stripping the prefix and postfix.
    This in turn should map to the corresponding `.desktop` file when available
 
 TODO: Define the name of slices that should be used.
-This could be `apps-<launcher>-<ApplicationID>-<RANDOM>.slice`.
+This could be `app-<launcher>-<ApplicationID>-<RANDOM>.slice`.
 
 TODO: Does it really make sense to insert the `<launcher>`? In GNOME I am
 currently using a drop-in to configure `BindTo=graphical-session.target`,
@@ -78,7 +87,7 @@ global default for all (graphical) applications.
 
  * Should application lifetime be bound to the session?
  * May the user have applications that do not belong to the graphical session (e.g. launched from SSH)?
- * Could we maybe add a default `apps-.service.d` drop-in configuration?
+ * Could we maybe add a default `app-.service.d` drop-in configuration?
 
 ## XDG autostart integration