Re: png in emacs 25 mingw64

[Eli Zaretskii]

> From: Stephen Leake <address@hidden>
> Cc: address@hidden,  address@hidden
> Date: Sat, 16 Apr 2016 15:34:16 -0500
> 
> 
> Question; exactly which path is searched for DLLs? I have two:
> 
> PATH from the parent process
> 
> exec-path after editing in ~/.emacs
> 
> The png image is opened well after ~/.emacs is processed, so does it
> look on the edited exec-path for the dll?
> 
> Or does the dll search take place during startup, in which case it is
> the parent PATH (or exec-path before editing in ~/.emacs).

DLL search is done by the OS.  See here:

  
https://msdn.microsoft.com/en-us/library/windows/desktop/ms682586%28v=vs.85%29.aspx

> >Are both 64-bit DLLs? Are they both MinGW DLLs?
> 
> I don't know how to tell.

The 'file' command is one way.

> > I don't understand why you (and others) use different PATH
> > arrangements to run different binaries, and have multiple versions of
> > support DLLs.  
> 
> If I want to use the Mingw distribution, I use that path.
> 
> If I want to use the Emacs pretest binary distribution, I use that path.

They are both MinGW programs, so I don't understand why you would need
to keep them apart.

> I have no idea how the Emacs pretest was built; simply assuming it is
> the same as my current Mingw installation is almost guarranteed to be
> false.

There's only one procedure to build Emacs on Windows, so yes, you can
assume that, and it will be almost certainly true.

> >Isn't it clear that by doing so you create your own DLL
> > hell?  
> 
> No, I'm avoiding it by not mixing distributions.

Suit yourself, but then don't be surprised when you have such
problems.

> Hmm. I do usually have Cygwin in the PATH as well

Now, _that_ you should keep separate from MinGW.