RFC: Cygwin 64 bit?

Corinna Vinschen corinna-cygwin@cygwin.com
Tue Jun 28 13:20:00 GMT 2011

On Jun 28 08:31, Earnie wrote:
> I've been reading with much interest the posts of this thread.  To help
> control which libraries are used by which programs and allow one Cygwin
> DLL to control both we could consider two differing entry points into
> the DLL, the existing one for 32bit and a new one for 64bit.  Cygwin
> would then know which pointer size to use because the initialization
> would be different.  Would this work, I don't know but thought I would
> throw the idea into the mix.

There's no reason for this and it also wouldn't work.  Windows does not
allow 64 bit processes to load 32 bit DLLs and vice versa.  However,
since each Cygwin DLL is local to the process and sharing of common data
is performed using handle inheritance, shared memory, named objects, etc.,
there's no reason that a 32 bit and a 64 bit Cygwin DLL couldn't work
together and constitute a single system with shared process lists, shared
tty lists, shared mounts, etc.


Corinna Vinschen                  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader          cygwin AT cygwin DOT com
Red Hat

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