Close the Outputter when the related source file is closed

[gmnr]

I'm trying to implement a way to close the outputter when the sourced buffer is closed.

This is what I got so far, but it's not working:

augroup QuitQuickRun
au!
    autocmd BufUnload * if (bufname("b:[quickrun output]")) || &buftype == 'nofile' | q | endif
augroup END

Is there a link between the buffer where the code executed is located and the related output that I can use?

Thanks in advance