Although there doesn’t appear to be any straightforward way to run command tools or scripts only on Efficiency cores, there are ways and means.
Two basic rules: M1 Macs run Arm-native code when it’s available, but won’t mix ARM-native and Intel code in the same process. Here are the details.
How can you run an app in a language different to that set for your system? Why doesn’t that work for command tools? And how difficult can a tool make controlling its environment?
How can you create and resolve Finder Aliases at the command line? And two further utilities you may find helpful for working with Aliases.
Running an AppleScript which tries to run a shell command with root privileges can fail. Here’s why, and what we can’t do about it.
How can you put four files with apparently identical names in the same folder? Here’s the secret, and the magic of Unicode.
Do you know how to customise the zsh shell now standard in Catalina? Here’s an excellent book which covers it in detail – and curious choice in 10.15.
Does using xattr flags disrupt Spotlight indexing, and how are those flags respected using different methods of copying a file?
I’m sure this used to be much easier in HFS+, but here’s a detailed set of instructions for making a bootable clone in High Sierra or Mojave, for an APFS disk.
Advice on preparing for and using Mojave for all who go beyond using standard off-the-shelf apps – scripting, automating, building from source, or full-blown Xcode development.