Hi,
 
What are you passing to the system() call?
 
A possible workaround is to call HPCICOMMAND instead...since that
doesn't use fork.
 
Fork is probably checking that you don't have any non-POSIX style resources
(e.g, outstanding CM-NM switches, or databases) before allowing the
fork to happen.  Why?  Because MPE doesn't know how to fork those
resources!   Memory, ordinary files...sure, no problem.  (Hmm, I haven't
tried forking with RIO, CIR, or CM KSAM files open.)
 
Of course, you could view the entire thing as a moral:
 
   Don't fork yourself.
 
SS