Re: Will not save file due to disk error
Posted: Wed Jan 17, 2018 8:56 pm
When you say "this virtual disk" which disk image do you mean? Because this is where my problem lies.adespoton wrote:I think you may be a bit confused about what you're doing when you emulate OS 9.
On your physical computer, you run an operating system that ties all the physical parts together and enables you to operate other software.
SheepShaver is the equivalent of that physical computer, but written in software so that it runs inside the physical computer's operating system.
Instead of a physical hard drive like a computer has, SheepShaver uses files that are stored on the physical hard drive. We call these "disk images" because they are a snapshot of exactly what we'd see on an equivalent physical drive.
So when you start up SheepShaver, it creates its virtual hardware, and one of the things it does is opens those disk image files as if they were physical drives. Once they're open, SheepShaver can read and write data there. Your MacOS9 drive is where the OS 9 operating system for the virtual computer (SheepShaver) is stored, and the operating system is loaded into SheepShaver's memory from this location, allowing SheepShaver to boot and display data on its virtual screen (which is then displayed on your computer's real screen).
When you install software on SheepShaver, you're installing it on one of these virtual disks that is then saved as a file on your actual computer. Since SheepShaver treats this file as an actual hard drive, it can read/write to it, load applications into SheepShaver memory from it, and run software.
When you save a file from an application running in SheepShaver, you should be saving it back to this virtual disk. The file that encompasses this disk is on your actual computer, so it is trivial to back up the entire file.
So you are saying that when I try to save my MacProject file to the Unix image, it may lose it's ability to be read because it loses a resource fork? (I don't know what an APFS folder is.) And if it does lose this resource fork then it is rendered unusable outside the Sheepshaver desktop?adespoton wrote: OS X has the ability built-in to also mount these virtual disk images as actual disks -- Disk Utility (and it's back end software) is used to manage these images. So you can create a volume in SheepShaver, and if you save it in HFS+ format, which OS X also recognizes, you can then open the image in OS X and manipulate the files as you see fit.
Because it's a bad idea to have this file open by both SheepShaver and OS X at the same time, and because SheepShaver also runs on Linux and Windows which can't read HFS+ disks, the authors of the software modified things slightly so that an actual folder on the host computer could be presented inside SheepShaver as a HFS+ disk. However, it isn't really an HFS+ disk, and so if anything unexpected is encountered when SheepShaver's OS's read and copy routines are accessing the disk, it will return an error and fail to work properly. The software enabling this feature was designed to work specifically with the OS 9 Finder, specifically for copying data files. Everything else that it does (like copying resource forks to HFS+ or APFS folders, etc.) is purely a bonus that may or may not work.
Woah! What is this? how could it even happen?adespoton wrote: So here's how things are laid out:
Your computer's Hard Disk
Your OS 9 disk image file
Your computer's memory
Running SheepShaver -- a subroutine that can read/write "file" objects to a folder on your computer's hard disk.
A direct connection to your OS 9 disk image file
So when running SheepShaver, you work on the virtual computer, and ignore your real computer. If you want to copy something off of SheepShaver, you have two options: save it to the virtual "Unix" disk, or shut down SheepShaver, and open up the virtual OS 9 disk in OS X.
Here you really lose me. I see no advantage to copying a file that isn't going to work anymore. So I'm new to time machine (I only acquiesced to it in the past two years.)adespoton wrote: If you want to back everything up, use Time Machine or some other backup software to back up the disk image. You can then revert to earlier versions of this disk image to load OS 9 and all the applications/files in that earlier state. It's just like making complete copies of your hard drive over time, and having them all available if you want to roll something back.
If you want to back up only a specific file, you copy it to the host computer and back it up like any other file.
No I don't really get this at all. If the resource fork is lost then the file is useless. How can a back up help? Or do I back up to the OS9 world and only operate there? What if OS 9 quits altogether? What happens to everything?adespoton wrote: Alternatively, CharlesSoft (Charles is a member on these forums) has generously made their OS 9-era backup software free for use, meaning that you could create another virtual disk image, load it into SheepShaver as well, and use the OS 9 backup software to back up files inside that environment to the secondary disk image. Your host computer, if you've got Time Machine running, will automatically back up all of these disk images again, every time they are modified.
Not really. I use Parallels and I must say that the files transfer in the same way as I did formerly with Sheepshaver. Right to file folders where I want them. And they open from there too (when I am in sheepshaver or parallels). Just like it used to with Sheepshaver. All these extra drives...what would be the benefit? I realize I am trying to keep something defunct alive. But there is still after all these years, no replacement for MacProject.adespoton wrote: Does that all make sense?