An ISPF session can be run in any installation-supported national language. Before starting ISPF with the ISPSTART command, a user must perform the necessary allocations. For example, command procedure ISPFE might be issued for an English session or ISPFG for a German session.

The same set of ddnames (ISPPLIB, ISPMLIB, ISPSLIB, ISPTLIB, and ISPPROF) must be allocated regardless of the command procedure used. At logon time, the necessary allocations for the national language at an installation can be performed by a CLIST or REXX logon procedure.

The language in which a session runs reflects the value (not always the full language name) in the read-only system variable ZLANG, which is available to dialogs running under ISPF. The default value for session languages is specified when ISPF is installed, and is discussed in z/OS ISPF Planning and Customizing. You can override the default session language with an alternate language keyword on the ISPSTART command. See the z/OS ISPF Dialog Developer's Guide and Reference for the exact syntax to use.

By specifying a default session language, the installation can ensure that both ISPF initialization messages and the normal session messages are in the default language. Even if you override the session default language with an alternate language using an ISPSTART language keyword, some of the first initialization messages, issued before the command scan, are in the default session language. However, any messages issued after processing of the ISPSTART parameters are in the language specified by the keyword.

If the terminal does not support DBCS, and the default language (or the alternate language selected by the language keyword) requires DBCS, ISPF uses English as the session language.

In cases where the session language requires DBCS, certain messages are always issued in English. These messages are:

• ISPF Main task abend.
• ISPF Subtask abend.
• The following required module for the selected language could not be loaded.
• ISPF command not allowed. You are already under ISPF.
• Invalid environment; TSO/E version 2.1 or later required.