Auto-reloading a file in VIM as soon as it changes on disk

Question

Assuming that a file doesn't have unsaved changes in the VIM buffer, I'd like it to reload automatically if the file changes on disk. The most frequent use case for this is when I update the working copy in which the file resides.

How can I achieve this?

Answer 1

In your ~/.vimrc:

set autoread

Answer 2

This is what worked for me

set autoread                                                                                                                                                                                    
au CursorHold * checktime  

The first line wasn't enough by itself. You can put in you .vimrc

credit to Phan Hai Quang

Answer 3

Autoread does not work correctly. The following works for me:

You need to first install the script from here.

I got the best results by calling the setup function directly, like so.

let autoreadargs={'autoread':1} 
execute WatchForChanges("*",autoreadargs) 

The reason for this, is that I want to run a ipython/screen/vim setup.

You can easily convert this into an enhanced version of view.

script the process..

mkdir -p ~/bin
cat <<`OUT` > ~/bin/vimviewer
#!/usr/bin/env sh
exec vim -n --cmd "source /home/bryan/.vim/.vimrc.watchforchanges | let autoreadargs={'autoread':1} | execute WatchForChanges('*',autoreadargs)" $@
`OUT`

chmod 755 ~/bin/vimviewer
vimview test.txt

Answer 4

vim-autoread plugin has worked for me so far:

vim-autoread

Automatically causes vim to reload files which have been written on disk but not modified in the buffer since the last write from vim. This enables a file open in vim to be edited using another application and saved. Upon returning to vim, as long as you haven't modified the file since the last change, the file will be automatically updated to reflect the changes made on disk, as though you had pressed :e manually.

Answer 5

from this answer (refering to an answer by PhanHaiQuang and a comment by @flukus)

One can run this oneliner from ex (whithin vim) when needed (or put each command in vimrc, for when log-files are opened.)

:set autoread | au CursorHold * checktime | call feedkeys("lh")

Explanation:
- autoread: reads the file when changed from the outside (but it doesnt work on its own, there is no internal timer or something like that. It will only read the file when vim does an action, like a command in ex :!
- CursorHold * checktime: when the cursor isn't moved by the user for the time specified in 'updatetime' (which is 4000 miliseconds by default) checktime is executed, which checks for changes from outside the file
- call feedkeys("lh"): the cursor is moved once, right and back left. and then nothing happens (... which means, that CursorHold is triggered, which means we have a loop)

Answer 6

There are some plugins listed here that might work depending on your version of Vim.

Another approach is to periodically send the checktime command to vim from an external process. Here's a ShellJS script to do this (requires shelljs-plugin-sleep, NeoVim, and nvr)

while (true) {
  sleep(15);
  var servernames = exec('nvr --serverlist').trim().split('\n');
  if (!servernames.length || !servernames[0]) {
    continue;
  }
  servernames.forEach(
    (sn) => exec(`nvr -c "checktime" --servername ${sn}`) );
}