Re: Emacs design and architecture. How about copy-on-write?

[Dmitry Gutov]

On 23/09/2023 14:23, Eli Zaretskii wrote:
> As a trivial example, any function that modifies a file-visiting
> buffer could prompt the user if the file was meanwhile modified on
> disk.  This prompt is completely out of control of any Lisp program
> which does something that modifies buffer text.  How do we handle
> these cases? their name is a legion.

Any function that prompts the user is not supposed to be fast. So it 
might as well acquire any number of global locks to do that.

So it's not an issue for concurrency - though it might become a 
stumbling block for the "concurrent redisplay" sub-project.