Kernel-side: kevent()

• EVFILT_PROC filter lets a process monitor other processes and get events when they fork(), execve(), or exit()

• want those events to be when the entire process does those, not when an individual thread does so

  • get more events than you care about

  • can't tell creation of threads from creation of child processes

• just move the struct klist from proc to process

• catch: librthread was using kevent() to determine when an exiting thread's stack could be freed

  • A: change threxit() to copyout a zero integer