0
$ glxgears -display :1
No protocol specified
Error: couldn't open display :1

$ glxgears -display :0
288 frames in 5.0 seconds = 57.491 FPS
292 frames in 5.0 seconds = 58.308 FPS
...

While glxgears is running, I ran xlsclients in a different terminal window:

$ xlsclients -display :0
alan-laptop  gnome-shell
alan-laptop  gsd-xsettings
alan-laptop  gsd-clipboard
alan-laptop  gsd-power
alan-laptop  gsd-color
alan-laptop  ibus-x11
alan-laptop  gsd-keyboard
alan-laptop  gsd-wacom
alan-laptop  gsd-media-keys
alan-laptop  firefox

System: Fedora 29, gnome-shell using Wayland.

$ rpm -q gnome-shell
gnome-shell-3.30.2-1.fc29.x86_64
$ rpm -q xorg-x11-server-Xwayland
xorg-x11-server-Xwayland-1.20.4-1.fc29.x86_64
$ rpm -q --whatprovides $(which xlsclients)
xorg-x11-utils-7.5-29.fc29.x86_64
$ rpm -q --whatprovides $(which glxgears)
glx-utils-8.4.0-1.fc29.x86_64
sourcejedi
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1 Answers1

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"xlsclients is a simple application which is listing the WM_CLIENT_MACHINE and WM_COMMAND properties set on top windows (ie. windows which are children of the root window or have a WM_STATE property)." -- mosvy.

According to ICCCM, the properties must be set by the client. I.e. if glxgears does not set them, it will not show up in xlsclients.

WM_CLIENT_MACHINE and WM_COMMAND are marked as obsolete by ICCCM. Also, it looks like they were only required as part of session management, which is not necessarily supported by all X clients.

This suggests xlsclients should be considered obsolete :-).

sourcejedi
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