(start_seq) can be used only in conjunction with a Language Environment environment
initialized by (init_sub_dp) function code. A return code 4 is set
for environments not initialized by (init_sub_dp).
(start_seq) minimizes the overhead between calls by allowing Language Environment to perform
as much activity as possible at the start of the sequence of calls.
Only (call_sub) or (call_sub_addr) invocations are allowed between
the (start_seq) and (end_seq) calls.
The same token must be passed for all
invocations of (call_sub) or (call_sub_addr) between the (start_seq)
and (end_seq) function codes. You can vary the routine invoked.
During a CEEPIPI call sequence, the user's CEEPIPI driver must
insure that the Language Environment® recovery routines are never invoked when a program
check or abend occurs in the user application code. One way to do
this is to run with Trap (ON,NOSPIE), and also establish an ESTAE
to handle errors when Language
Environment is not active.