document updated 15 years ago, on Oct 26, 2008

This is for booting an .ISO file. i.e. an actual file that's sitting on a disk somewhere... not something that's been properly burned to a CD-ROM.

The only way to do this is for the booter to create a "virtual CD/floppy/hard drive". Since this is obviously a huge hack, it has a few caveats.

MEMDISK, usually used to create standard-sized virtual floppies, but it can create a virtual hard disk too. (but not ISOs)
GRUB4DOS's ISO emulation (also search for "CDROM emulation" here)
IsoEmu

Alternate approaches exist:

Copy the contents of each .ISO into its own partition. This is much less hacky and more straightforward than most other methods.
Copy the contents of each .ISO into a separate subdirectory. But you have to do more hackery to boot into them in their expanded form. Every distro needs slightly different things done to it to make it boot, and a few simply aren't able to boot out of subdirectories.
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