Why doesn't OSX Activity Monitor show the processes I started?

I'm using fork and execv to start child processes. If I run htop then I can find those processes. However, OSX Activity Monitor doesn't show them, even if I have it set to show all processes. Why is that?

The S column in htop show Z for all of my processes. What does that mean? Could that have something to do with i开发者_运维百科t?

The Z in htop means the process is a "zombie". This means that the process has completed running and wants to die, but the parent process has not yet called wait() to obtain the child process exit code.

It's possible that the OS X Activity Monitor does not show zombie processes.