VSAM macro descriptions and examples

This chapter contains VSAM macro formats and examples.

The macros that work at assembly time allow you to specify subparameter values as absolute numeric expressions, character strings, codes, and expressions that generate valid relocatable A-type address constants.

The macros that work at execution allow you also to specify these values as:

Register notation, where the expression designating a register from 2 through 12 is enclosed in parentheses. For example, (2) and (REG), where REG is a label equated to a number from 2 through 12.
An expression of the form (S,scon), where scon is an expression valid for an S-type address constant, including the base-displacement form.
An expression of the form (*,scon), where scon is an expression valid for an S-type address constant, including the base-displacement form, and the address specified by scon is indirect—that is, it gives the location of the area that contains the value for the subparameter.

For most programming applications, you can use register notation or absolute numeric expressions for numbers, character strings for names, and register notation or expressions that generate valid A-type address constants for addresses. Subparameters with GENCB, MODCB, SHOWCB, and TESTCB, gives all the ways of coding each parameter for the macros that work at execution time.

You can write a reentrant program only with execution-time macros. Use of list, execute, and generate forms of VSAM macros, describes alternative ways of coding these macros for reentrant programs. This chapter describes the standard form of these macros.