Macos opening ghostty with open -n command opens it in a new process

[nadeemkhedr]

Summary

I am using Karabiner to set some global shortcuts to launch new instances (windows) of applications

I have a shortcut that executes this command

open -n "/Applications/Ghostty.app"

What I expect:
I expect this command to create a new window in ghostty

What happens:
This creates a new process (two ghostty apps running) and opens a new window

Why raise it as a question, not a bug?

docs for -n for the open command is:

always open a new instance of application

But this behavior is different than other applications, I have been using this cmd with other applications like browsers and other terminals, and what happens is that it always open a new window not create a new process

[nadeemkhedr]

A workaround until/if this is fixed:

You can run this AppleScript:

tell application "Ghostty"
	if it is running then
		activate
		tell application "System Events" to keystroke "n" using {command down}
	else
		activate
	end if
end tell

This will open Ghostty if its closed, and will create a new window if it's open

[00-kat]

browsers

I'm not 100% sure about macOS, but in my experience, Firefox doesn't support opening multiple instances, which may be relevant (of course, I don't know what browser you use; Ii'm just mentioning this in case you use Firefox).

[timvisher]

But this behavior is different than other applications, I have been using this cmd with other applications like browsers and other terminals, and what happens is that it always open a new window not create a new process

This is the expected behavior of open … -n, IIUC. Chrome specifically is an odd-ball in this arena since it's tabs are all separate processes which is why it works the way you're describing.

I'm not sure which terminal you're talking about but Terminal.app, iTerm 2, Kitty, and Alacritty all open multiple application instances on my box.

When using this sort of logic in the future you probably want to switch to the standard

open -a <Application Name> -n

rather than what you're doing as well. Not only will this find Applications not installed in /Applications but it's also ever so slightly shorter.

[canTuncPekkan]

nice catch, I missed it by thinking the flag -n was a -a

[nadeemkhedr]

open -a "Ghostty.app" -n still opens ghostty as a new instance for me

[timvisher]

open -a "Ghostty.app" -n still opens ghostty as a new instance for me

Sorry to be clear, that's what's supposed to happen. As you point out in OP

docs for -n for the open command is:

always open a new instance of application

The only application I'm currently aware of that doesn't behave this way is Google Chrome and that's only because Google Chrome runs every tab as a separate process (this was one of its big selling points in the beginning because a crash in one tab didn't bring down the whole browser).

As I pointed out:

I'm not sure which terminal you're talking about but Terminal.app, iTerm 2, Kitty, and Alacritty all open multiple application instances on my box.

So I'm not sure what other terminals you're testing in but at least for me the behavior matches other terminals and what macOS claims open … -n should do.

[nadeemkhedr]

@timvisher

Most of the terminals I used had options for this

WezTerm -> By default works as a single instance only
Kitty -> you can add --single-instance options and would work like that

Even Ghostty has the option to run a single instance only on GTK

I don't know if the correct solution is to add a single instance flag, for me this is not a blocker because i was able to find a workaround with the applescript, but if I couldn't it would have been one

[timvisher]

Ah so Kitty requires a special flag to inform it not to launch a separate process if one's running already I guess.

WezTerm may be taking the same approach that Google Chrome is using. I haven't tried that terminal at all.

Even Ghostty has the option to run a single instance only on GTK

I think what's important here is that that's the default behavior on most linux distros I've seen which is why the gtk option makes sense there. If you run an application again in linux distros you tend to get a separate process. In those contexts Chrome is again the odd ball in that each new process becomes a separate tab.

Regardless it's not the default behavior on macOS and IMO applications that violate that expectation should not be emulated in an application that seeks to feel like a native app.

[timvisher]

Also you may want to follow #2353 since I think a direct way to manage Ghostty GUI components is what you're looking for rather than for open -a Ghostty -n to do what you're asking it do.

[gknops]

For Terminal.app I have this handy function in my fish config:

function n
	
	echo "
tell application \"Terminal\"
	activate
	do script with command \"$argv\"
end tell
" | osascript

end

That allows me to write n someCommand arg1 arg2 and have that happen in a fresh window. Would love to see this for Ghostty.

[paolomainardi]

Following this discussion because I am suffering the same issue with iterm2 and skhd I used to have this config:

❯ cat .config/skhd/skhdrc

cmd - return : osascript -e 'tell application "iTerm2" to create window with default profile command ""' || open -na iTerm
cmd + shift - return : open -n -a "Google Chrome"

And that osascript allows to open new windows in the same instance, instead of creating multiple iterm2 instances.

[mitchellh]

A new instance is the intended behavior of -n as noted here: #3563 (comment) Other applications are behaving odd, not us. :) There's probably some other way to script this but otherwise will be #2353.

[paolomainardi]

Thank you for your reply, @mitchellh. I believe other apps allow this by prefixing the osascript, as shown in the example I reported here: #3563 (comment).