3 ms·

NEVER, EVER mangle your raw images, specially if you want to dd/tar them back to the original machine. Also, as a golden rule on IT, specially on emulation,

by anthk 3y ago

NEVER, EVER mangle your raw images, specially if you want to dd/tar them back to the original machine. Also, as a golden rule on IT, specially on emulation, NEVER do unexpected changes to the original media, be disk images, CD-roms, BIOS dumps or any other firmware. If you want to make changes for interop, do it in RAM as a volatile change or write the metadata anything else on the emulator config directory. The mentiones change is not useful, it really sucks. The move was one of the words turds ever done to historical computing and data preservation. Period. The purpose of emulation is to run and preserve the original systems -unchanged- by design. The user is the one who commits the changes while he is running the emulated system from the inside, and not the emulator. The goal is to preserve the data back and forth, not to ruin it.

mlyle 3y ago
> mangle your raw images, specially if you want to dd/tar them back to the original machine dd back to the original media is no problem with stuff post-pended; dd will complain that there's an extra block at the end, but other than that, all's good. > The goal is to preserve the data back and forth, not to ruin it. A big part of the point of this change is to prevent you from attaching devices "wrong" in ways that are likely to cause the emulated environment to corrupt them. You can't do that in RAM, and it's better if it is in the same file.
- anthk 3y ago
  >You can't do that in RAM, and it's better if it is in the same file. No, that's a setting for the config file, or per machine by default in the settings, but never in the media itself. The old media should be pristine. If the user mangles some media because it attached some cd image as an RP disk under a Vax, it's his issue, is not an issue of the emulator.
  - mlyle 3y ago
    It's not "old media". It's a disk image in some format. Before it was just a raw disk image. Now it's a container format for a disk image--- that happens to generally work as a raw disk image, too. Either one keeps the original data pristine.
    - anthk 3y ago
      No, you are wrong. Emulators should never touch the original data format save up for converting it at will, as qemu can do by using qemu-img.
      - mlyle 3y ago
        That's a belief you have, but it isn't something that one can be "wrong" about.

by anthk 3y ago

mlyle 3y ago

> mangle your raw images, specially if you want to dd/tar them back to the original machine dd back to the original media is no problem with stuff post-pended; dd will complain that there's an extra block at the end, but other than that, all's good. > The goal is to preserve the data back and forth, not to ruin it. A big part of the point of this change is to prevent you from attaching devices "wrong" in ways that are likely to cause the emulated environment to corrupt them. You can't do that in RAM, and it's better if it is in the same file.

anthk 3y ago
>You can't do that in RAM, and it's better if it is in the same file. No, that's a setting for the config file, or per machine by default in the settings, but never in the media itself. The old media should be pristine. If the user mangles some media because it attached some cd image as an RP disk under a Vax, it's his issue, is not an issue of the emulator.
- mlyle 3y ago
  It's not "old media". It's a disk image in some format. Before it was just a raw disk image. Now it's a container format for a disk image--- that happens to generally work as a raw disk image, too. Either one keeps the original data pristine.
  - anthk 3y ago
    No, you are wrong. Emulators should never touch the original data format save up for converting it at will, as qemu can do by using qemu-img.
    - mlyle 3y ago
      That's a belief you have, but it isn't something that one can be "wrong" about.