Prevent quickfix buffer from writing to a file

[jeromedalbert]

I have this handy bit of code that autowrites files when focus is lost:

augroup improved_autowrite
  autocmd!
  autocmd FocusLost,BufLeave * call Autowrite()
augroup end

function! Autowrite()
  silent! wa
endfunction

However, this also writes the quickfix buffer to a file if I have it open and change focus. For now I was able to mitigate with

function! Autowrite()
  if bufname('%') =~ 'quickfix-' | return | endif
  silent! wa
endfunction

But this only works if the current buffer is the quickfix list. If I switch to another buffer, it will still write the file.

Is there some way to prevent this? Maybe somehow prevent the quickfix list to ever be written to a file?

[stefandtw]

Here are two things you could try:

• Use :w instead of :wa and keep excluding quickfix- buffer names. Should still work. Assuming you don't use operations that modify buffers in multiple windows simultaneously.
• Use :update instead of :write. If you absolutely need to write buffers in multiple windows, you could do :windo update.

[jeromedalbert]

Thanks for the pointers!

I want to keep using :wa so that autowriting works even when switching tabs. And windo :update will sometimes write to the quicklist buffer when the buffer is modified.

After some poking around, I ended up with the following code:

function! Autowrite()
  for tabnum in range(tabpagenr('$'))
    for bufnum in tabpagebuflist(tabnum + 1)
      if bufname(bufnum) =~ '^quickfix-' | return | endif
    endfor
  endfor
  silent! wa
endfunction

This basically disables autowriting if the quickfix list is open anywhere in Vim. This is good enough behavior for me, as I never leave the quickfix list open for very long. I could further improve by falling back to single-file :w autowriting if needed.