Provided by: systemtap-doc_2.3-1ubuntu1.4_all 

NAME
function::target_set_pid - Does pid descend from target process?
SYNOPSIS
target_set_pid(pid:)
ARGUMENTS
pid
The pid of the process to query
DESCRIPTION
This function returns whether the given process-id is within the “target set”, that is whether it is a
descendant of the top-level target process.
SystemTap Tapset Reference March 2016 FUNCTION::TARGET_SET(3stap)