A program that is invoked in a TSO/E environment may require information from the user profile table (UPT). For example, the language a user has selected is defined by the UPTLANG field of the UPT. The program, however, might not have access to the command processor parameter list (CPPL), which contains the UPT address. A program that does not have access to the CPPL can access the UPT though the protected step control block (PSCB). The PSCB contains the PSCBUPT field, which points to the UPT. MVS™ provides the mapping macro IKJPSCB for the PSCB.

You can access the PSCB by issuing the EXTRACT macro to request the address of the PSCB. For information about the EXTRACT macro, see z/OS MVS Programming: Authorized Assembler Services Reference EDT-IXG.

Figure 1 illustrates the two ways a program can access the PSCB.

Figure 1. Chaining of Control Blocks and Fields to the UPT

Figure 1 shows the control blocks and fields that support the path to the UPT. MVS provides the mapping macros for these control blocks. Table 1 relates the mapping macros to the control blocks shown in Figure 1.