I've been trying to find a good way to install PureOS on a Macbook Pro. So far I've only seen one very convoluted solution that involves installing a trial version of Windows 10. I'm looking for a more direct solution to get the Macbook's EFI to recognize and boot from a PureOS live USB.
Preferably, I'd like to find a generalized solution to make a Mac-bootable USB from any .iso file, but something that works specifically for Debian-based distros would be fine too.
If the .iso contains all the right software, correctly configured, to boot a Mac from a flash drive (see note at bottom of this Answer), then you can do this:
Convert the .iso to a .dmg:
hdiutil convert -format UDRW -o filename.dmg filename.iso
Connect your USB drive to your Mac.
Make sure you've got all the data you care about off of all partitions/volumes of the entire drive.
Use the output of this command to figure out which disk # your USB drive shows up as:
diskutil list
You're looking for an identifier like /dev/diskN.
NOTE THE NUMBER AND USE IT IN PLACE OF N BELOW.
Unmount all volumes from this disk to prepare it to be overwritten
diskutil unmountDisk /dev/diskN
Use dd to write the .dmg to the flash drive (note that we need the "rdisk" version of the disk device for this command; don't forget the 'r'!)
sudo dd if=filename.dmg of=/dev/rdiskN bs=1m
Eject the disk so we can use it somewhere else:
diskutil eject /dev/diskN
Note that if your .iso is set to boot like an ISO9660 CD-ROM instead of a hard drive, there's a Perl script called "isohybrid.pl" that you can run against your .iso to make it capable of hybrid booting (like either a CD-ROM or a hard drive). So you may need to run that against your .iso before you do any of the steps above.
I have successfully performed these steps on a "System Rescue CD" bootable Linux .iso and booted MacBooks from it.
