As is stated in the documentation: Input register information Before issuing the IEANTCR callable service, the caller does not have to place any information into any register unless using it in register notation for a particular parameter, or using it as a base register.
with the analogous information provided for IEANTRT and IEANTDL. Perhaps a better approach would have been, upon seeing this, to ask "may I trust the documentation?" <snip> I believe it has been the intention of the MVS team over the past several years to make all of the basic assembler macro-invoked services independent of the caller's R13. </snip> Not true. There is no such intention. A service that is stacking-PC-entered or SVC-entered will naturally typically not need a caller-provided save area. Callable services that wind their way to an SVC or PC as the means of getting into the system are often similar. Callable service that run in the state and key of the caller that wind their way to a "BAKR" would not need a caller-provided save area. Callable services that run in the state and key of the caller but avoid BAKR (whether for environmental or performance reasons) would. What is considered, in some cases, is that services that might be used for obtaining dynamic storage not need either to require a save area or provide a non-register-only parameter list. The IEANTRTR macro was introduced in z/OS 2.2, for example. It is a register-only analog of the IEANTRT callable service. By implementing a register-only interface, it becomes more possible to use name/token retrieve for locating a storage area for which you stashed its address in the appropriate name/token. Peter Relson z/OS Core Technology Design ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
