[RFC] Preserve native Windows quoting with CYGWIN=noglob

[Jon Turney]

On 25/08/2026 19:26, Erik Demaine wrote:
> Dear Cygwin developers,
> 
> I am a long-time Cygwin user (30 years or so), but am new to its 
> development side, so let me know if I'm missing any protocol or best 
> practices.

No, this is fine.  Sorry about the delay in replying!

> Cygwin's command-line argument processing when called from a non-Cygwin 
> process is a complex subject with lots of history (see below for 
> links).  I'd like to propose (and happy to implement) a relatively small 
> change:
> 
> PROPOSAL: CYGWIN=noglob mode handles quotes the same as CYGWIN=glob mode

Thanks very much for this detailed and thoughtful review of the state of 
this thorny problem.

[...]

> 
> My proposal is to narrow the scope from the 2021 rewrite:
> 
> 1. Decode a native Windows command line using the same quote/backslash
>     rules regardless of CYGWIN=[no]glob.
> 2. Let allow_glob control only wildcard, bracket, brace, and tilde
>     expansion.
> 3. Preserve the existing glob-enabled and Cygwin-parent behavior.
> 
> If full backward compatibility is a requirement, then we could add 
> another flag parallel to [no]glob, something like [no]quote.  I haven't 
> thought about the best design for this, given that the current 
> implementation conflates the two issues, but I imagine we could fogure 
> it out through discussion.

Hmm... I think the question is "is the existing handling of quotes so 
broken than nobody can be relying on it"? In which case, we can safely 
classify it as a bug and just fix it.

It seems that way to me, but this isn't a feature I actually have an 
experience using.


> Would a focused patch along these lines be welcome?

Very much so!


It would probably help people reason about the behavioural change this 
implies, if there was a small test plan, or even an automated test.