Build Custom FreeDOS Boot ISO

Modify FreeDOS ISO image to run DOS .exe files like BIOS updates, HDD diagnostics, etc.

Instructions

Grab the repo:

git clone https://github.com/bfritz/freedos-custom-iso.git
cd freedos-custom-iso

Download and prepare the base ISO image:

curl -O http://www.ibiblio.org/pub/micro/pc-stuff/freedos/files/distributions/1.0/fdbasecd.iso
sudo mount -o ro fdbasecd.iso /mnt

rsync -avSP /mnt/* image/
sudo umount /mnt

# patch to exit the installer early
patch -p0 < setup.patch

Drop files into image/extras/. Best to pre-extract zip files.

Recreate the ISO:

# sudo pacman -S mkisolinux
(cd image; sudo ./mkiso.sh)

Burn the ISO, for example with wodim:

# sudo pacman -S cdrkit
wodim -v -data -eject freedos_custom.iso

Test with:

# sudo pacman -S qemu
qemu-system-i386 -cdrom freedos_custom.iso

Credit

Based on Sean Reifschneider's article on tummy.com.