The QSTRUP program is normally used to start subsystems. You should be able to retrieve the source for this program and modify the program as necessary. This is the correct way to proceed with this. I would try the following :-
RTVCLSRC PGM(QSTRUP) SRCFILE(yourlib/QCLSRC)
If I understand your question correctly, you are trying to understand how QINTER and QBATCH get started. They are
started when you start QCTL. There is a system value QCTLSBSD which contains the controlling subsystem for the
system. If the system value contains QCTL, that is the controlling system that is started upon IPL. When running
System 36 envinronment, you would have QBASE in that substystem value.
I’ve always run S/36 environment stuff under QCTL – always worked OK for me.
Appreciate both answers (:-)