Is there a way running processes without '/bin/sh -c'?

[n-connect]

Hello everyone,

Is it possible to run any or all processes/programs from hyprland.conf set with exec exec-once directly, eg. cut out the /bin/sh -c portion from the equation?

With nwg-dock-hyprland, nwg-drawer, nwg-menu, they are starting the selected apps with /bin/env -S which leaves no footprint in memory/cpu usage, nor they are just not left in an additional process in the process list/tree. Of course there could some hard reasons I'm not aware about yet why they are there like environment to do so, hence this post. :)
But I'm wondering if it is possible to cut them out.

In my case various environment values are set (env GTK, QT & gsettings) in the hyprland.conf, so I can start lighter apps up-to heavy ones (browsers and alike) with /bin/env -S . Until now without issue and having no additional /bin/sh -c wrapping aorund them. BUT they've started from the nwg-* apps, which in return still started with /bin/sh -c.

Anyway, long story short: is it possible to get a rid of those /bin/sh -c prefixes in case of the exec/exec-once statements?

I've checked the source there are at least 5 points, where it has been hardcoded (Edit list fixed & updated):

• src/signal-safe.hpp -> 'writeCmdOutput' used in CrashReporter.ccp
• src/helpers/MiscFunctions.cpp 'execAndGet', used at multiple places, but fixed binaries and parameters
• src/xwayland/Server.cpp -> runs Xwayland with /bin/sh -c
• src/managers/KeybindManager.cpp -> 'CKeybindManager::spawnRawProc' in its own code files .hpp .cpp, no fixed binaries
• hyprpm/src/core/PluginManager.cpp -> 'execAndGet' used with pciconf and lspci
• hyprpolkitagent runs Xwayland app 'Gparted' with /bin/sh -c wrap, but 'gnome-text-editor' without wrap

Thanks

[mlpeter33]

I think for some programs u can just do: exec = /usr/bin/program so they don't execute with shell

In the case of env variables:

env = var,value
exec = /usr/bin/program

but this will apply the env globally, even if not needed, and will apply until hyprland load it configs meaning they wont affect hyprland itself

Also there are some processes that require shell

[n-connect]

Yes, tried it , but no difference:

• if is just the binary name,
• or with full path.
  Hyprland runs it with '/bin/sh -c' in both cases.

As the link points to the sources with my best guest:
src/managers/KeybindManager.cpp

I do have ways within a Hyprland session to start programs without it already, but outside the hyprland.conf's exec/exec-once. The idea is to have it from the get go from Hyprland itself for every process part of the Hyprland session. Maybe I need to modify the source, test it out if it works / ask for it to be configurable.

[mlpeter33]

I see. I might test it too, now I'm curious lol

[n-connect]

Okay, so answering my question

Reading after the difference of /bin/sh -c vs /bin/env -S wrapping and the difference and parameters of execl() vs system() .c/.cpp call.

As a result made a quick 'n dirty modification in the v.0.47.2 source release and built a Hyprland where /bin/sh -c -> /bin/env -S changes has been done:

• hyprland-source/src/xwayland/Server.cpp : line 323
• hyprland-source/src/managers/KeybindManager.cpp: line 972

As a first round Hyprland seems to works on user level, and got rid of all the additional /bin/sh -c wrappings. Every process runs direclty including Xwayland.

• 'xdg-desktop-portal' failed to start: Failed to create app chooser proxy: Error calling StartServiceByName for org.freedesktop No skeleton to export
• 'hyprpolkit' failed to start: missing WAYLAND_DISPLAY
• xdg-desktop-portal-hyprland not even checked...
• and waybar failed with this error: Error calling StartServiceByName for org.freedesktop.portal.Desktop: Timeout was reached

Second round after moving back from env-mod to original check the environment differences and services and go back again to my env-moded version, suddenly:

• 'xdg-desktop-portal' & 'hyprpolkit' started as services
• waybar not starting, behaves strange for keybings, but running manually from terminal works
• EDIT: the bind for printscreen also does not work :D bind = , Print, exec, grim -g "$(slurp)" but from terminal its ok
• also, it turned out nwg-dock-hyprlan pinned apps started differently comparead to nwg-drawer. The latter works always -> this one also using /bin/env -S wrapping
• plus why some apps missing its icon in nwg-dock-hyprland (thanks @nwg-piotr for the nwg-* apps!)

Some additional tests necessary,checking them across reboots etc. I think some environment value setup is missing with removing /bin/sh -c. If this is the only problem it can be added to hyprland.conf as a default value/part of the sample hpyrland.conf.

Keep using the mod-env version till figuring out, additional tests appreciated.

[n-connect]

So doing the two modification in Hyprland replacing /bin/sh -c to /bin/env -S in:

• hyprland-source/src/xwayland/Server.cpp : line 323
• hyprland-source/src/managers/KeybindManager.cpp: line 972

Created some other issue causing missing environment variables in systemd's --user slice -> in return xdg-desktop-portal-hyprland & xdg-desktop-portal service won't start and waybar plus hyprpolkitagent won't start either. Missing systemd variables:

• XDG_CURRENT_DESKTOP=Hyprland
• QT_QPA_PLATFORMTHEME=qt6ct

Quick manual oneliner fix:

systemctl --user set-environment XDG_CURRENT_DESKTOP=Hyprland;systemctl --user set-environment QT_QPA_PLATFORMTHEME=qt6ct;systemctl --user import-environment DISPLAY QT_QPA_PLATFORMTHEME WAYLAND_DISPLAY XDG_CURRENT_DESKTOP

Than starting the services:

systemctl --user start xdg-desktop-portal-hyprland;systemctl --user start xdg-desktop-portal;systemctl --user start hyprpolkitagent

If you want to verify, check xdg-desktop-portal-hyprland xdg-desktop-portal xdg-desktop-portal-gtk hyprpolkitagent

Question is where is the place in Hyprland for the systemd environment variable sets, to make sure what makes this difference and fix it. Until then one additional line in hyprland.conf should fix this:

exec-once = systemctl --user set-environment XDG_CURRENT_DESKTOP=Hyprland;systemctl --user set-environment QT_QPA_PLATFORMTHEME=qt6ct;systemctl --user import-environment DISPLAY QT_QPA_PLATFORMTHEME WAYLAND_DISPLAY XDG_CURRENT_DESKTOP

[n-connect]

It seems the dispatchExecOnce() call from ConfigManager.cpp do make the systemd and/or dbus calls for environment. The call been made in Renderer.cpp upon a monitor connected.
Somehow in the build with the "patched" version to /bin/env -S seems not to be applied, even if their call in the hyprland.log. Maybe I need to run them wrapping them into their own /bin/env -S .
Also the env. unsetting happens in CCompositor::cleanEnvironment() in Compositor.cpp

Once that's cleared it can be PR-d into mainline.

[n-connect]

So the quick 'n dirty patch or change or jump from the /bin/sh -c wrappings now have a fix. I'm happy with the result level, however I'm usually using about 10-20 GUI apps regularly only, so tests are welcome -> in general and let say 90% and above in my case, so I'll share my build / the difference in my repo fork for testing purposes. Normal GUI apps works, ,the ones they need elevation also (using hyprpolkitagent), Xwayland/Xorg based to. Everything else runs in or from terminal

Edit:
The fix (not a final solution) was, to add the lines seems not applying after they tried to ran from dispatchExecOnce() call from ConfigManager.cpp into a little shell script and make it the first exec-once statement in hyprland.conf: exec-once = $HOME/.config/hypr/scripts/systemd-env.sh That way everything comes up/works in my little DE like setup Hyprland session including the autohide capable waybar.

#!/bin/bash
if [ `ps -p 1 -o comm=` == "systemd" ]; then
    /bin/env -S systemctl --user import-environment DISPLAY WAYLAND_DISPLAY HYPRLAND_INSTANCE_SIGNATURE XDG_CURRENT_DESKTOP QT_QPA_PLATFORMTHEME PATH XDG_DATA_DIRS &&
    hash dbus-update-activation-environment 2>/dev/null &&         
    systemctl --user import-environment DISPLAY QT_QPA_PLATFORMTHEME WAYLAND_DISPLAY XDG_CURRENT_DESKTOP;            
fi

Fixed script above: following the logic from ConfigManager.cpp to either run the first line or the second depending if the underlying system is systemd based or not.

Possible bug: it seems both lines actually ran based on hyprland logs. however the lines adds same environment variables, but the first adds more plus utilize them over dbus too. Fixme: I'm not a C++ dev unfortunately.

The two non-systemwide things did not work first and were part of my DE kind setup:

• my oneliner script saved into direcly hyprland.conf's as a bind -> is about controlling/running/restarting waybar in companion with autowaybar -> one can put the oneliner into a 2 lines shell script
• screenshot with this grim -g $(slurp) -> here I need to figure out things with $() expression and env, till then hyprshot can be used

The piece I found not working comes from the Linux distro:

• I can't run Wireshark from nwg-menu, cause of and interesting oneliner involving pkexec -> no fix just running it from cli, not from nwg-menu

All in all, this /bin/env -S replacement finally works, but grim -g $(slurp) shows there's still things to clarify...

[n-connect]

A second modified version created to avoid big breaking changes in Hyprland startup/config, where the following files modified:

• Hyprland/src/xwayland/Server.cpp "runXWayland()" : /bin/sh -c replaced
• Hyprland/src/managers/KeybindManager.cpp "spawnRawProc()" : /bin/sh -c replaced
• Hyprland/src/config/ConfigManager.cpp "dispatchExecOnce()" : /bin/sh -c added before systemctl line

Edit:

• Hyprland/src/config/ConfigManager.cpp "handleEnv()" : /bin/sh -c added before systemctl line
• Hyprland/src/Compositor.cpp "cleanEnvironment()" : /bin/sh -c add before systemctl line

With that the the previously created additional script is not necessary anymore - Hyprland starts normally, xdg-desktop-portal-gtk starts. The xdg-desktop-portal-hyprland can be started without errors, but manually, the env vars applied.

Edit2:
The #ifdef USES_SYSTEMD selection is differently functioning, as I've thought first. I'm still not sure why the 3 commands that chained into one after another with success as dependency, are broken into a different 3 lines and only the first 2 ones surrounded with the #ifdef USES_SYSTEMD #endif block

Edit3: these systemctl blocks want to be a oneliner, while at the same time, handle if Hyprland compiled with systemctl support or not. The line-breaks could be some kind of C++ formatting/style rule make it quite unreadable. All in all, the issue why it does not executed could lie in the fact of the oneliner approach: using the built-in shell execute logic with && between the commands can be the reason why they are not excuted correctly.

if ()
   handlerawexec("",
#ifdef USES_SYSTEMD
  command1 && hash co
  mand2 &&
#endif
  command3);

Remaining issue is, that the "~" is not parsed in paths, and "$HOME" must be used. Finally for screenshot bind this is what I've use instead of the original: bind = , Print, execr, /bin/sh -c 'grim -g "$(slurp)"' until find out a better/final solution. Ironic, I know :)

I'll make a PR from this stage, to see how it can be even better.

[n-connect]

A streamlined version of Hyprland build commands - works with 0.50.1 too. This does the job getting rid of /bin/sh -c s - beside an exec-once script into your hyprland.conf:

cd /tmp/;git clone --recursive https://github.com/hyprwm/Hyprland && \
cd Hyprland && git checkout v0.50.1 && \
sed -i 's|"/bin/sh", "/bin/sh", "-c"|"/bin/env", "/bin/env", "-S"|g' src/xwayland/Server.cpp && \
sed -i 's|"/bin/sh", "/bin/sh", "-c"|"/bin/env", "/bin/env", "-S"|g' src/managers/KeybindManager.cpp && \
make all && make install && \
tar -cvf /tmp/Hyprland_v0.50.1.tar.gz -T build/install_manifest.txt

There's a Dockerfile ongoing for full Hyprland, its ecosystem and Wayland friends build here, its for Debian:testing. A debian:stable is ongoing, but Trixie marked release date 2025 Aug 9, so maybe I'll wait it out :)

The final systemd / dbus variables script to run:

#!/bin/bash
if [ `ps -p 1 -o comm=` == "systemd" ]; then
  /bin/env -S systemctl --user import-environment DISPLAY WAYLAND_DISPLAY HYPRLAND_INSTANCE_SIGNATURE XDG_CURRENT_DESKTOP QT_QPA_PLATFORMTHEME PATH XDG_DATA_DIRS &&
  hash dbus-update-activation-environment 2>/dev/null &&
  systemctl --user import-environment DISPLAY QT_QPA_PLATFORMTHEME WAYLAND_DISPLAY XDG_CURRENT_DESKTOP;
fi

Add the above like this as kind of the first exec-once statement into your hyprland.conf:

## /bin/env -S fix for missing systemd env variables (XDG_CURRENT_DESKTOP=Hyprland & QT_QPA_PLATFORMTHEME=qt6ct ... etc.)
exec-once = $HOME/.config/hypr/scripts/systemd-env.sh