WSL run linux from windows without spawning a cmd-window

Here's a simpler solution that requires a WSH-based helper script, however:

wscript .\runHidden.vbs bash -c "DISPLAY=:0 xmessage 'hello, world'"

To apply @davv's own launch-in-background technique to avoid creating a new bash instance every time:

One-time action (e.g., at boot time): launch a hidden, stay-open bash window. This spawns 2 bash processes: the Windows bash.exe process that owns the console window, and the WSL bash process (owned by the WSL init singleton), which is then available for servicing background commands.

wscript .\runHidden.vbs bash # hidden helper instance for servicing background commands

For every X Window-launching command: Terminate each command with & to have it be run by the hidden WSL bash instance asynchronously, without keeping the invoking bash instance alive:

wscript .\runHidden.vbs bash -c "DISPLAY=:0 xmessage 'hello, world' &"

---

runHidden.vbs source code:

' Simple command-line help.
select case WScript.Arguments(0)
case "-?", "/?", "-h", "--help"
  WScript.echo "Usage: runHidden executable [...]" & vbNewLine & vbNewLine & "Runs the specified command hidden (without a visible window)."
  WScript.Quit(0)
end select

' Separate the arguments into the executable name
' and a single string containing all arguments.
exe = WScript.Arguments(0)
sep = ""
for i = 1 to WScript.Arguments.Count -1
  ' Enclose arguments in "..." to preserve their original partitioning.
  args = args & sep & """" & WScript.Arguments(i) & """"
  sep = " "
next

' Execute the command with its window *hidden* (0)
WScript.CreateObject("Shell.Application").ShellExecute exe, args, "", "open", 0

Even when launched from a GUI app (such as via the Run dialog invoked with Win+R), this will not show a console window.

If you've configured your system to execute .vbs scripts with wscript.exe by default (wscript //h:wscript /s), you can invoke runHidden.vbs directly, and if you put it in your %PATH%, by filename (root) only: runHidden ....

Note that use of the script is not limited to console applications: even GUI applications can be run hidden with it.

So I just made this workaround for now. I really hope that there's a better way than this, but here it goes:

In the command prompt that lives purely to keep WSL alive, I have this script running:

wsl_run_server

#!/bin/bash
set -e
nc -kl 127.0.0.1 15150 | sh

And then I have this command to execute commands in background:

wsl_run_command

if ! pidof -x bin/wsl_run_server; then
    echo wsl_run_server isnt running!
    exit 1
fi
echo \($@\) \& | nc localhost 15150

from windows I then call:

bash -c "DISPLAY=:0 ~/bin/wsl_run_command xmessage hello"

There's another simple solution, it requires an external executable though. It has no dependencies and was recommended by aseering on GitHub.

you can launch bash via run.exe: run.exe bash.exe -c "<whatever Linux command>". (run.exe is available here: http://www.straightrunning.com/projectrun/ , make sure you download the 64-bit version, the 32-bit version will not be able to find or run bash).

With run on the search PATH, you can just call

run bash -c "DISPLAY=:0 xmessage hello"