I was amused to find the following in the z/OS C/C++ runtime library reference

#include <signal.h>

int __superkill(pid_t pid);

where the documentation includes:

“The __superkill() function generates a more robust version of the SIGKILL signal to
the process with pid as the process ID. The SIGKILL will be able to break through
almost all of the current signal deterrents that can be an obstacle to the normal
delivery of a SIGKILL and the resulting termination of the target process.”

The obvious question, not mentioned in the documentation, is whether or not this API can kill zombies?