Support for EWMH-compliant WMs

[b0o]

The EWMH specification defines a set of interactions between window managers and external tools like docks, status bars, and other desktop-environment related utilities.

An incomplete list of EWMH-compliant window managers is (via Wikipedia):

• aewm
• awesome
• i3
• xmonad (needs to be turned on in the config)
• wmii
• goomwwm
• spectrwm
• Blackbox
• Compiz
• CTWM (as of 4.0.0)
• edewm
• Fluxbox
• FVWM (via a plugin prior to v2.4 and native support from v2.5)
• JWM
• KWin
• Metacity
• Openbox
• Enlightenment (E16 and E17)
• evilwm
• fwm (via a plugin)
• interfacewm
• matchbox
• Sawfish (not completely)
• wmfs
• Xfwm

There is a Rust package, xcb-util, which provides a wrapper around the Linux libxcb-util (X protocol C-language Binding), including a wrapper around the libxcb-util EWMH implementation.

A quick glance at the package leads me to believe it provides the necessary functionality to create an EWMH implementation of wmfocus.

[svenstaro]

Yeah, that's my hope as well. Do you wanna take a stab at this?

[b0o]

@svenstaro I've honestly never written Rust, but I may give it a go if I have some free time.

[svenstaro]

I don't really know how to get a list of visible windows on all currently visible desktops using xcb/xlib and there is no obvious way that I can see. Any idea?

[b0o]

Hmm, good point. I can only figure out how to determine the active desktop, list all desktops and the windows on them, but not necessarily a straightforward way to definitively determine if any given window is visible.

By playing around with wmctrl, xdotool, and xprop, and examining their sources, I can determine:

• The root window:
  • xprop -root: https://gitlab.freedesktop.org/xorg/app/xprop/blob/master/dsimple.c#L209
  • strategy:
  • Use xlib's RootWindow or DefaultRootWindow function (man AllPlanes(3))

    • Display *disp = XOpenDisplay(NULL); 
      Window *root = DefaultRootWindow(disp);

• A list of all Desktops:
  • wmctrl -d: https://github.com/dancor/wmctrl/blob/master/main.c#L1063
  • strategy:
    1. Current desktop can be determined by examining _NET_CURRENT_DESKTOP on the root (and/or possibly _WIN_WORKSPACE?)
    2. Names of all desktops can be determined by examining _NET_DESKTOP_NAMES on the root
  • Notes:
    • Unsure how to determine if a desktop is visible?
• A list of all Windows:
  • wmctrl -l: https://github.com/dancor/wmctrl/blob/master/main.c#L1323
    • list of windows including window ID, desktop ID, window name
  • strategy:
    1. List of Window IDs can be accessed via _NET_CLIENT_LIST on the root
    2. xdotool seems to imply that you can determine if a given Window is visible by examining its _WM_STATE
       • https://github.com/jordansissel/xdotool/blob/08c8e2d6cad60a69ce415499e34865157a1b66fd/xdo.h#L418-L422
       • https://github.com/jordansissel/xdotool/blob/89cb4cf5fd8b27058491fda8294b184f70b31076/xdo_search.c#L194-L201

This is about all the time I have time to dig in right now, maybe this gives you some ideas?

[t-wissmann]

I don't really know how to get a list of visible windows on all currently visible desktops using xcb/xlib and there is no obvious way that I can see. Any idea?

You simply need to iterate over all windows mentioned in _NET_CLIENT_LIST (all windows, as specified by EWMH) and for each window check whether the first entry of WM_STATE is 1 ("NormalState", i.e. not Iconic or Withdrawn; specified by ICCCM). This gives you all visible windows.

[rdiaz02]

In https://www.reddit.com/r/bspwm/comments/qf0jd5/switching_and_swapping_windows_with/hi9ppyy/ @ortango has provided code that allows wmfocus to be used from bspwm . (This is also available with the additional needed modifications in Cargo.toml and main.rs from https://github.com/rdiaz02/wmfocus/tree/stdin ) .

[svenstaro]

I'd definitely accept a patch but with bspwm I suppose the bspwm client tool should be called in get_windows(). I suppose overall it wouldn't be too hard to integrate. The posted patch does things in a fairly awkward way and needs to be done differently.

[rdiaz02]

Sure, I understand. However, I am not the author of the patch, and I know no Rust, and almost no bspc, so I won't be able to contribute this anytime soon. The intention of posting it here and placing it in a repo was so that other people searching around could find it (either for using as is, or for preparing a patch that could be integrated).

[svenstaro]

I might try but then again I don't really run bspwm anymore and I can't support the feature so well. It'd be much better added and maintained by someone who uses it as their daily driver.

[rdiaz02]

That would be great (I plan on moving to bspwm around Christmas, so I could test it and I assume many other bspwm users would be interested). And, of course, I understand that ideally this would be added and maintained by someone who uses bspwm daily.

[DeafMan1983]

Sorry it is old. I know far. I would like to suggest about libxcb and xcb's extensions from gitlab should to compile with --enable-static --enable-shared if you have to test with Rust then you would like to publish as end-usable program without required libxcb or xcb's extensions ( You just can compile with gcc -Wl,-Bstatic lxcb -lXau -lXdmcp -lxcb-util (....) -Wl,-Bdynamic -lc (....) means other xcb's extensions like xcb-image, xcb-cursor, xcb-composite etc... they should to be statical in Rust program and you won't to get worry.

Or I have made with C# Dotnet 7.0/8.0 and it is very beautiful single executable.

Please remember that: You can check in terminal: LD_LIBRARY_PATH=. ./your_rust_program If your_rust_program throws errors cause your_rust_program doesn't build with statical libxcb.a etc ....

I hope you understand my suggestion and my suggestion helps you. Sorry my bad English...

Best regards!