How to avoid "file has changed" warning when writing buffer?

Question

I am using system() to change a buffer's file. I apply the same change to the buffer itself. I can't just reload the buffer because there are other unsaved changes.

When I come to write the buffer, Vim gives me:

WARNING: The file has changed since reading it!!!
Do you really want to write to it (y/n)?

I do really want to write to it.

How can I avoid this warning?

I have tried adding a FileChangedShell autocmd which doesn't do anything, but it does not get fired for system() calls. So I added a silent execute ':!', which seems to trigger the autocmd, but the screen gets all messed up – and vim still shows the warning.

Any ideas would be greatly appreciated!

Answer 1

One solution is to store the contents of the buffer, reload the file (to make vim happy), then restore the contents.

let lastline = line('$')
let bufcontents = getline(1, lastline)
edit!
call setline(1, bufcontents)
if line('$') > lastline
  execute lastline+1.',$:d _'
endif