Building IGZUOPT and IGZQUOPT runtime option control block

The IGZUOPT (for AMODE 31) and IGZQUOPT (for AMODE 64) modules refer to load modules that you build and provide during COBOL program execution time. These modules are assembler programs that use the assembler macro IGZXOPT.

The IGZXOPT macro is an assembler macro that is used in an assembler program that must be assembled and then linked into a load module called either IGZUOPT or IGZQUOPT applications. This load module, IGZUOPT or IGZQUOPT, must be available in a load module PDS that appears in a STEPLIB DD statement for your running application. The COBOL runtime searches for this module when needed and based on the module's settings, sets runtime option control flags. If no such module is found, IBM® defaults will prevail.

Important: You should only add this option control block load module into the STEPLIB stream for applications that are meant to use the specified options. In particular, when you use the VSAMDYNAMICDIR option, you should be aware of which applications should take advantage of this feature because it has impact on performance.