Writing a program that cannot be killed except by reboot

[Felix Lee]

> If a process is ptraced, a SIGKILL delivered to it will cause it to
> stop and awaken its parent.

Hmm.  Then it may be possible for two procesess to mutually ptrace
each other (using PTRACE_ATTACH) such that they both intercept and
ignore KILL signals.  You can still stun the processes if you can
deliver signals to both of them quickly enough.
--
Felix Lee	flee at cs.psu.edu