Convert Downloaded El Capitan.app to bootable iso

makeOSXiso.sh

# Maybe use this: https://github.com/geerlingguy/macos-virtualbox-vm

#!/bin/bash

#taken from http://www.insanelymac.com/forum/topic/308533-how-to-create-a-bootable-el-capitan-iso-fo-vmware/

# Mount the installer image
hdiutil attach /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/SharedSupport/InstallESD.dmg -noverify -nobrowse -mountpoint /Volumes/install_app

# Create the ElCapitan Blank ISO Image of 7316mb with a Single Partition - Apple Partition Map
hdiutil create -o /tmp/ElCapitan.cdr -size 7316m -layout SPUD -fs HFS+J

# Mount the ElCapitan Blank ISO Image
hdiutil attach /tmp/ElCapitan.cdr.dmg -noverify -nobrowse -mountpoint /Volumes/install_build

# Restore the Base System into the ElCapitan Blank ISO Image
asr restore -source /Volumes/install_app/BaseSystem.dmg -target /Volumes/install_build -noprompt -noverify -erase

# Remove Package link and replace with actual files
rm /Volumes/OS\ X\ Base\ System/System/Installation/Packages
cp -rp /Volumes/install_app/Packages /Volumes/OS\ X\ Base\ System/System/Installation/

# Copy El Capitan installer dependencies
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

# Unmount the installer image
hdiutil detach /Volumes/install_app

# Unmount the ElCapitan ISO Image
hdiutil detach /Volumes/OS\ X\ Base\ System/

# Convert the ElCapitan ISO Image to ISO/CD master (Optional)
hdiutil convert /tmp/ElCapitan.cdr.dmg -format UDTO -o /tmp/ElCapitan.iso

# Rename the ElCapitan ISO Image and move it to the desktop
mv /tmp/ElCapitan.iso.cdr ~/Desktop/ElCapitan.iso

# Remove temp file
rm /tmp/ElCapitan.cdr.dmg