dynamic conpty loading

[Thomas Wolff]

Am 21.11.2025 um 17:46 schrieb Corinna Vinschen via Cygwin:
> Hi Thomas,
>
> On Nov 21 16:46, Thomas Wolff via Cygwin wrote:
>> Am 21.11.2025 um 11:04 schrieb Takashi Yano via Cygwin:
>>> On Sun, 5 Oct 2025 10:15:55 +0200
>>> Thomas Wolff wrote:
>>>>>> The procedure seems to be:
>>>>>> try LoadLibrary("conpty.dll"), (if not successful, fallback to
>>>>>> GetModuleHandle("kernel32") instead) to retrieve GetProcAddress for
>>>>>> CreatePseudoConsole, ResizePseudoConsole, ClosePseudoConsole, and
>>>>>> then somehow (?) use those while calling CreateProcess.
>>>>>> The latter is woven into the cygwin library and I don't think it's a
>>>>>> good idea to clone that out of cygwin for a patched process creation
>>>>>> in mintty.
>>>>>>
>>>>>> My question/suggestion:
>>>>>> Can a cygwin mode switch to a selected conpty library instead of the
>>>>>> default one please?
> Where do you expect this conpty.dll to reside?
>
> If we do something like that, I would suggest to make sure that this
> conpty.dll is in a well-defined place. /bin or /lib might be a good
> idea. And if it exists in this defined place, it will be used by Cygwin.
>
> We can tweak the autoload mechanism to allow a primary DLL and a fallback
> DLL, that drops the need to set the CYWIN env var.
>
> The mintty package could contain a post-install script, or some other
> script in /bin to allow a user with admin rights downloading the latest
> (or the most sensible) conpty.dll from MSFT.
>
> Would that make sense?
>
>
> Corinna
>
That makes much sense, yes, thank you. /bin/conpty.dll would probably be 
a good place.
Thomas