hdiutil attach /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/SharedSupport/InstallESD.dmg -noverify -nobrowse -mountpoint /Volumes/ElCapitan
hdiutil create -o /tmp/ElCapitan.cdr -size 7316m -layout SPUD -fs HFS+J
hdiutil attach /tmp/ElCapitan.cdr.dmg -noverify -nobrowse -mountpoint /Volumes/install_build
asr restore -source /Volumes/ElCapitan/BaseSystem.dmg -target /Volumes/install_build -noprompt -noverify -erase
rm /Volumes/OS\ X\ Base\ System/System/Installation/Packages
cp -rp /Volumes/ElCapitan/Packages /Volumes/OS\ X\ Base\ System/System/Installation/
cp -rp /Volumes/ElCapitan/BaseSystem.chunklist /Volumes/OS\ X\ Base\ System/BaseSystem.chunklist
cp -rp /Volumes/ElCapitan/BaseSystem.dmg /Volumes/OS\ X\ Base\ System/BaseSystem.dmg
hdiutil detach /Volumes/ElCapitan
hdiutil detach /Volumes/OS\ X\ Base\ System/
hdiutil convert /tmp/ElCapitan.cdr.dmg -format UDTO -o /tmp/ElCapitan.iso
mv /tmp/ElCapitan.iso.cdr ~/Desktop/ElCapitan.iso
macOS Sierra：
hdiutil attach /Applications/Install\ macOS\ Sierra.app/Contents/SharedSupport/InstallESD.dmg -noverify -nobrowse -mountpoint /Volumes/Sierra
hdiutil create -o /tmp/Sierra.cdr -size 7316m -layout SPUD -fs HFS+J
hdiutil attach /tmp/Sierra.cdr.dmg -noverify -nobrowse -mountpoint /Volumes/install_build
asr restore -source /Volumes/Sierra/BaseSystem.dmg -target /Volumes/install_build -noprompt -noverify -erase
rm /Volumes/OS\ X\ Base\ System/System/Installation/Packages
cp -rp /Volumes/Sierra/Packages /Volumes/OS\ X\ Base\ System/System/Installation/
cp -rp /Volumes/Sierra/BaseSystem.chunklist /Volumes/OS\ X\ Base\ System/BaseSystem.chunklist
cp -rp /Volumes/Sierra/BaseSystem.dmg /Volumes/OS\ X\ Base\ System/BaseSystem.dmg
hdiutil detach /Volumes/Sierra
hdiutil detach /Volumes/OS\ X\ Base\ System/
hdiutil convert /tmp/Sierra.cdr.dmg -format UDTO -o /tmp/Sierra.iso
mv /tmp/Sierra.iso.cdr ~/Desktop/Sierra.iso
