Open System Services Programmer's Guide

from the OSS shell to suspend a job, all processes in the group associated with that job can receive
the signal to stop. (Signals can be sent to an individual process or to an entire process group.)
A Guardian process cannot belong to a process group or session, which is a collection of one or
more process groups.
Example 1 provides code to demonstrate the use of some of the OSS group information functions
including getgrent(), endgrent(), setgrent(), getgrgid(), and getgrnam().
34 Overview of the OSS Programming Environment