Blocking debugging is easy, just have 2 processes running and have them ptrace each other. Then have the processes do a handshake every so often. The handshake has to include some proof of life. If a handshake is missed the process aborts. The beauty of this approach is that the 2 processes can do the handshake by ptrace, there doesn't need to be an external message.
A limitation in the kernel is that only 1 process can attach to another process.
pjford
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution