Provided by: systemtap-doc_2.9-2ubuntu2_all 

NAME
function::pstrace - Chain of processes and pids back to init(1)
SYNOPSIS
pstrace:string(task:long)
ARGUMENTS
task
Pointer to task struct of process
DESCRIPTION
This function returns a string listing execname and pid for each process starting from task back to the
process ancestor that init(1) spawned.
SEE ALSO
tapset::pstrace(3stap)
SystemTap Tapset Reference April 2016 FUNCTION::PSTRACE(3stap)