Aliases created in Mini vMac do not work elsewhere?

About Mini vMac and all other 68k emulators, including SoftMac, Executor, and MESS.

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gingerbeardman
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Aliases created in Mini vMac do not work elsewhere?

Post by gingerbeardman »

When I create an alias in Mini vMac, move that alias to my real Macintosh Classic (or in Basilisk II), and then double click it I get an error "Please insert the disk: Macintosh HD".

Is this because the internal disk in Mini vMac is presented as a floppy, and the internal disk in my real Mac is a hard drive? Is there any way to fix this either in Mini vMac or on my real Mac?

The interesting thing is that the aliases are not broken (so there's nothing to repair) but rather just pointing to a disk that is not present.

Thoughts appreciated, thanks!

matt
• BasiliskII on iPad Pro 12.9": Macintosh IIci 32MB + System 7.5.5 + Deneba artWORKS & UltraPaint
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Ronald P. Regensburg
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Re: Aliases created in Mini vMac do not work elsewhere?

Post by Ronald P. Regensburg »

An alias in classic MacOS does not work with file paths, but works with the original file it points to. Move the file to a different location and the alias still works. Copy the alias and the alias copy still works. But replace the original file with a copy and the alias stops working.

The copy of the alias looks for the original file on the original disk. No way to change that behaviour. You will need to create a new alias.
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adespoton
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Re: Aliases created in Mini vMac do not work elsewhere?

Post by adespoton »

Classic Aliases (not the SymLink types) use the HFS/HFS+ serial number of the file in combination with the serial number of the disk it's on. This means that you can move the alias anywhere, but the original file it is linked to is tied both to the partition/drive it's on and the file entry in the BTree table.

The upside here is that the aliases can be copied anywhere, and the file can move anywhere on the same volume and still be referenced. The downside is that this is NOT the same file if it's on a different volume in the same location. And since Mini vMac presents the images as floppy disks, they'll have different volume identifiers than when the same image is mounted in Basilisk II or on the desktop of another OS.
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Re: Aliases created in Mini vMac do not work elsewhere?

Post by gingerbeardman »

@adespoton you are almost there!

Earlier I used ResEdit to find the difference between two Aliases, one created on vMac and one not. Witness:

Image

If I change the 05 to 00 in the alias created on vMac, it will open on real hardware (and in Basilisk II)

This byte represents the type of volume (fixed or ejectable) on which the alias is located.

There's a very handy extension called Follow Finder Alias that allows these aliases to work regardless http://umich.edu/~archive/mac/system.extensions/init/

...but, unfortunately on my real Classic it gives an address fault on startup!

Though it works on my Mini vMac Classic setup?
• BasiliskII on iPad Pro 12.9": Macintosh IIci 32MB + System 7.5.5 + Deneba artWORKS & UltraPaint
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adespoton
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Re: Aliases created in Mini vMac do not work elsewhere?

Post by adespoton »

That sounds like an extension that should be bundled with Mini vMac, or maybe built in!

This does make me think that maybe I should talk Paul into just changing the mass storage handler to change that bit based on image size (larger than 1.44MB, set the storage type to that used for the HD20 even when using the Sony driver to access it. This isn't the HDSC system, so no SCSI implementation needed.
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gingerbeardman
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Re: Aliases created in Mini vMac do not work elsewhere?

Post by gingerbeardman »

I sent Paul some feedback earlier today, let's see what he says.

What you suggest would be best, as I'm still stuck for a solution for those aliases on real hardware.

If you can influence him, feel free!
• BasiliskII on iPad Pro 12.9": Macintosh IIci 32MB + System 7.5.5 + Deneba artWORKS & UltraPaint
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