Color me confused. So of the two parts, delivery and execution let me know where I'm off base. Does the INT not get sent to the non-child PID or is the INT somehow not honored by the non-child of the same pid? And how is this different from using kill(1) from the command line where it doesn't matter whether the process is a child or not. I did a quick read of kill from perlfunc and Signals from perlipc and I didn't see anything about INT not being sent to non-child processes. So what's the scoop here, how did you come up with that?

Update: then I wasn't wrong. Unstated was the assumption that normal user control functions so you can only kill your own processes. It's just unlikely that a given user ends up with another process at the same UID, not actually prohibited some how.

__SIG__
use B;
printf "You are here %08x\n", unpack "L!", unpack "P4", pack
  "L!", B::svref_2object(sub{})->OUTSIDE;
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