I've been using Vim 6.3 (specifically, gvim) for years (and plain old vi for decades before that). One nice feature was that autoread would detect if the file permissions changed. I made use of that feature with the following autocmd,
autocmd BufWritePre * if &readonly | !p4edit <afile>
where p4edit is a shell script that, among other things, runs "p4 edit" on the file to open it in my Perforce sandbox and make it writable. This script would be invoked if I "w!" wrote the readonly file.
In Vim 6.3, vim knew from then on that the file was writable, but now with Vim 7.4, this is no longer the case. Subsequent write attempts still require "w!", and the p4edit script is reinvoked each time.
Likewise, if I "p4 submit"ed any files I had open in gvim windows, the next time I went to one of those windows, gvim would notice that the file was once again readonly.
Is there a way to get the old behaviour back?