FreeBSD-10.3-RELEASE-i386-memstick.img installer changes contents of USB flash drive

[Warren Block]

On Tue, 4 Oct 2016, Ian Smith wrote:

> > I'd think you could just dd(1) the contents of the single installer disk
> > partition into a big-enough MBR partition.  Repeat for each image, then use
> > boot0cfg.
>
> Sure, for old-style raw BSD images, but that won't work for images with:
> 1) PMBR, 2) primary GPT, 3) efifat partition, 4) gptboot partition then
> 5) the UFS partition - which is all we want to copy to a bootable BSD
> slice - then 6) 1M(??) swap.  We need to use /boot/boot bootblocks for
> each slice; still, it may be easy to locate and dd just that partition
> out of the mdconfig'd image - or mount it and copy; some tests needed.

What is the difficulty?  1-4 are not needed for an MBR disk anyway. 
The UFS partition is the same either way, and gpart can install the 
bootcode that lives in the start of a UFS filesystem also.

It would be easier to not use boot0, which is not very powerful. 
Syslinux or Grub can multiboot with a lot more options, although you do 
need to make room for them.