Create bootable Mac OS iso

Create ISO from DMG

Create bootable Sierra.iso:

#!/bin/bash

# mount InstallESD.dmg to /Volumes/install_app
hdiutil attach /Applications/Install\ macOS\ Sierra.app/Contents/SharedSupport/InstallESD.dmg -noverify -nobrowse -mountpoint /Volumes/install_app

# create Sierra.cdr.dmg
# hdiutil create -o /tmp/Sierra.cdr -size 6200m -layout SPUD -fs HFS+J
hdiutil create -o /tmp/Sierra.cdr -size 7316m -layout SPUD -fs HFS+J

# createmount Sierra.cdr.dmg to /Volumes/install_build
hdiutil attach /tmp/Sierra.cdr.dmg -noverify -nobrowse -mountpoint /Volumes/install_build

# restore BaseSystem.dmg to /Volumes/install_build (will renamed to "/Volumes/OS X Base System")
asr restore -source /Volumes/install_app/BaseSystem.dmg -target /Volumes/install_build -noprompt -noverify -erase

rm /Volumes/OS\ X\ Base\ System/System/Installation/Packages

cp -rp /Volumes/install_app/Packages /Volumes/OS\ X\ Base\ System/System/Installation/
cp -rp /Volumes/install_app/BaseSystem.chunklist /Volumes/OS\ X\ Base\ System/BaseSystem.chunklist
cp -rp /Volumes/install_app/BaseSystem.dmg /Volumes/OS\ X\ Base\ System/BaseSystem.dmg

hdiutil detach /Volumes/install_app
hdiutil detach /Volumes/OS\ X\ Base\ System/
hdiutil convert /tmp/Sierra.cdr.dmg -format UDTO -o /tmp/Sierra.iso

mv /tmp/Sierra.iso.cdr ./Sierra.iso
rm /tmp/Sierra.cdr.dmg