Deliver additional files in a convenient way for versions without CD filesystem support

[rakslice]

The post 2.2.1 Dec 2021 rebuild version (https://technologists.com/notes/2008/01/10/a-brief-history-of-dell-unix/) Dell Unix includes CD filesystem support necessary to access additional_contents we put on the disk in Rock Ridge format. But the common 2.2 version floating around doesn't have it -- it has the CD block device, which we use successfully to install the base system, but then there's no way to mount a Rock Ridge or even plain ISO filesystem on it, as far as I can tell.

However our ability to modify the install scripts means we can put additional stuff on the on-disk filesystem.

• Maybe we can generate a script to dd the files out from their known offsets
  • We can presumably work them out from the build CD image somehow after mounting it on the system that built it
  • This will require some trickery to get the script into the image if we have to generate it after creating the image
  • Maybe for simplicity we just support extracting one tar from a fixed offset

[rakslice]

Is the CD filesystem support just an installable for the older version?

According to the manual page for pfs_mount, it is "the Portable File System Package (PFS)" by "Young Minds, Inc." and was obviously commercial software, available in different versions. https://web.archive.org/web/19970603131206/http://www.ymi.com/products/supported_list.html Was it just available to vendors to build into their products as seen in 2.2.1?