Modifying the SVC table at execution time (SVCUPDTE macro)

After the IPL, the SVC table can be dynamically modified by authorized users via the SVCUPDTE macro. For example, authorized subsystems such as VTAM® can alter the SVC table when the subsystem starts and restore the table when the subsystem terminates. For additional flexibility, the EPNAME and EXTRACT parameters of the SVCUPDTE macro allow the authorized user to dynamically associate SVC numbers with entry points of SVC routines.

NOT Programming Interface Information An SVC update recording table is maintained in parallel with the SVC table. This table provides a record of changes to the SVC table. Entries are created whenever a change is made to the SVC table with IEASVCxx parmlib member statements or the SVCUPDTE macro. End NOT Programming Interface Information