Mac app sandboxing and forkpty()

Question

I'm looking to sandbox an app to comply with the March 1st sandboxing requirement of the Mac App Store. My app includes a built-in terminal emulator which utilizes a forkpty() call to launch processes in a pseudo-tty environment. Unfortunately, this call fails under the sandbox with the error "Operation not permitted", although the fork() call works just fine. Presumably the forkpty() call requires read/write access to the /dev/ directory to create a pseudo-tty (according to the man page). I've tried adding a temporary sandboxing entitlement (com.apple.security.temporary-exception.files.absolute-path.read-write) with read/write access to /, and I now can indeed read and write files anywhere on the file system, but the forkpty() call still fails with the same error. Does anyone know how I might get forkpty() to work under the sandbox?

My app is a programming text editor with a built-in terminal emulator and file browser, so it essentially needs to have access to the entire file system. Apart from the forkpty() problem, this temporary entitlement seems to do what I need. But will Apple accept an app with such a loosely defined temporary exception entitlement?

Thanks in advance guys. I really hope I can get this sandboxing up and running so I continue to distribute my app through the App Store.