HP 3000 Manuals HP 3000 Manuals
Restrictions There are some additional limitations. Currently, software interrupts are not available directly from COBOL or on remote files. If the process contains privileged code, the interrupt handler must be privileged to handle interrupts from it, or else an ABORT 22, Invalid stack marker, will occur. If the code you want to interrupt is privileged, then your interrupt handling procedure must also be executing in Privileged Mode. If the code to be interrupted is non-privileged, then your interrupt handler can be either privileged or non-privileged. The following restrictions apply to Compatibility Mode code only. In CM, your interrupt handler may reside in any system Segment Library. The hierarchy of Segment Libraries is as follows: PROG = User program segments GSL = Group segment libraries PSL = Public segment libraries SSL = System segment library A routine on one level can call routines on that level or below. However, this distinction does not apply to software interrupts. So your interrupt handler can reside in any library and interrupt code in any other library. There is one exception: code in the SSL (System Segment Library) cannot be interrupted. The reason is that MPE XL routines cannot be interrupted, and the system cannot distinguish between the MPE XL routines and the other routines residing in the SSL.