SPIE and ESPIE exit routines and data areas should reside in storage that can be referenced by all subspaces. This ensures that a SPIE or ESPIE routine has addressability to all required data areas, regardless of the subspace environment in which the program interruption occurs.

Because SPIE and ESPIE routines cannot percolate, they always receive control in the subspace environment that was in effect when the error occurred in the mainline program. SPIE and ESPIE routines are explained in z/OS MVS Programming: Authorized Assembler Services Guide.