Z provides detection of dereferencing 0 via PER ZAD, which is controlled by SLIP ZAD on z/OS.
Jim Mulder z/OS Diagnosis, Design, Development, Test IBM Corp. Poughkeepsie NY "IBM Mainframe Assembler List" <[email protected]> wrote on 09/09/2020 05:30:32 PM: > From: "Charles Mills" <[email protected]> > To: [email protected] > Date: 09/10/2020 11:34 AM > Subject: Re: Deep Cuts > Sent by: "IBM Mainframe Assembler List" <[email protected]> > > I think faulting on dereferencing 0 is a hardware function and yes, > most hardware does so. Not so Z, where traditionally much of the > "API" is chained off of the PSA. > > Z faults on references to (in the assembler vernacular; de- > referencing in the C vernacular) x'800' and immediately above, > right? (Do I have that address right?) > > Z faults (usually, for an application) on writes to 0: *((char > *)NULL) = 'A'; > > Charles
