Subject: bug#78340: [PATCH] New option for comp *.eln file name by the file timestamp of *.el

From: Eli Zaretskii <[email-masked]>
Date: Mon, 12 May 2025 22:11:02 +0300

> From: Lin Sun <[email-masked]>
> CC: "[email-masked]" <[email-masked]>, "[email-masked]"
> 	<[email-masked]>
> Date: Mon, 12 May 2025 16:38:06 +0000
> msip_labels:
> 
> From: Eli Zaretskii <[email-masked]>
> Sent: Monday, May 12, 2025 02:24 PM
> > ... which will probably be slow on Windows
> > for the same reason computing the content hash is slow...
> 
> I want highlight reading a .el file will call windows api OpenFile/ReadFile.../CloseFile.
> Here is an example that Emacs try to read the .el file to calculate the .eln name, it had called "ReadFile()" 6 time to read full content.

Yes, because Emacs reads files in chunks of 32KB.

> If Emacs uses timestamp, just call Getattribute() function, will reduce counts on windows file api calling.

I tried to explain why relying on time stamps is not reliable enough
in this case, it brings too high risk of loading an incompatible .eln
file.

In Emacs, we value correctness before speed.