Re: [PATCH] Report any problems with loading the VGA driver for PPC Macintosh targets

[Programmingkid]

> On Aug 30, 2021, at 5:47 PM, BALATON Zoltan <balaton@eik.bme.hu> wrote:
> 
> On Mon, 30 Aug 2021, Peter Maydell wrote:
>> On Mon, 30 Aug 2021 at 21:29, Programmingkid <programmingkidx@gmail.com> 
>> wrote:
>>> I found out that there are two pc-bios folders. One in the root directory
>>> and one in the build directory. QEMU is looking in the pc-bios folder
>>> located inside the build folder. The qemu_vga.ndrv file is only located
>>> in the root directory pc-bios folder. I think a good solution to this
>>> issue is to first remove one of the pc-bios folders. I'm not sure if it
>>> is just me who has two pc-bios folders or if everyone does.
>> 
>> Having two pc-bios folders is expected. The one in the source tree is
>> the one which has the files we actually carry around in git. The one
>> in the build tree is created by 'configure' and populated with symbolic
>> links back to the files in the source tree. We need this one because
>> the QEMU executable doesn't (and shouldn't) know where the source tree is:
>> when it is looking for files it will look in places relative to the
>> location of the executable itself (ie relative to the build tree)
>> as well as places set by configure (used when you install QEMU and
>> its various supporting files).
>> 
>> The reason qemu_vga.ndrv is not in the pc-bios folder in the build
>> tree is because when that file was added we forgot to add handling
>> for it in configure. I'm not sure why nobody else has fallen over
>> this in the intervening 3 years: running QEMU from the build tree
>> will never find the file, and it will not be installed via
>> 'make install' either.
> 
> This file is a driver for MacOS and not many people run that old OS. Those 
> who do probably use Howard's binaries and follow his guides that tell you to 
> use -L pc-bios on command line. I always wondered why that's needed when it 
> should find it by default but this explains it and probably also your 
> question why nobody complained.
> 
> Regards,
> BALATON Zoltan

This does sound like a good explanation. I am pretty sure I was able to use my 
Mac OS 9 VM without the -L option in the past and still have many video 
resolutions available.