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On Thu, 2 Oct 2014 21:38:36 +0000 (UTC), Grant Edwards wrote: |
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> > They did something, but it's not particularly special. All they did |
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> > was run isohybrid (from syslinux) on the ISO image. It uses unused |
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> > space at the start of the DVD ISO specification that is normally left |
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> > blank to hold a partition table so the image can be copied to a USB |
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> > drive and appear as a partitioned disk. |
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> |
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> There must be a little more to it than that. Does it also install |
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> along with a parition table some bootloader code that knows where/how |
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> to boot the ISO boot image? [After a little googling] It also |
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> installs MBR bootloader code that knows how to find/load isolinux.bin: |
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> |
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> http://www.syslinux.org/wiki/index.php/Isohybrid |
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Yes, the unused space contains the MBR; partition table and bootloader. |
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Plus it adds some more code at the end of the image. |
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I was also wrong in stating I use isohybrid for the LXFDVDs. I used to |
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but since switching to using GRUB to boot the DVDs, there is no need for |
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it. GRUB bootable DVD ISOs can boot from USB sticks by default. |
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That's the trouble with writing scripts to take care of routine tasks, |
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you forget when you are actually doing beyond running the script. |
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> Interestingly, it also created a second EFI boot partition which |
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> exists inside the main parition. |
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That must be a UEFI bootable disc. ISOs can have all sorts of strange |
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setups, I have to make the LXFDVDs readable on a Mac, which results in |
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an HFS+ filesystem being nested inside the ISO one. |
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-- |
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Neil Bothwick |
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Become a gynaecologist, look up a friend today. |