IBM OS/390 manual Environments, 18.4.1 VSE/ESA Environment, 18.4.2 VM/ESA Environment, Power

18.4 Environments

The system under which REXX procedures run is assumed to include at least one environment for processing commands. An environment is selected by default on entry to a REXX procedure.

You can change the environment by using the ADDRESS instruction:

address	cms	/*	VM/ESA CMS environment */
address	POWER	/*	VSE/ESA POWER host command environment */

address TSO ²ALLOC F(SYSOUT) DSN(my.dsn) SHR² address DOS ¢ DIR MDV1.ALL¢

TSO ISPF dialog invocation:

address ISPEXEC ²SELECT CMD(%myexec) ²

You can find out the name of the current environment by using the ADDRESS built-in function. ADDRESS() returns the name of the environment to which commands are currently being submitted.

if address() = ¢ CMD¢ then /* OS/2 environment */

The underlying operating system defines environments external to the REXX procedure.

The environment selected depends on the caller. For example if a procedure is called from CMS, the default environment is CMS. If called from an editor that accepts subcommands from the language processor, the default environment may be that editor.

ADDRESS temporarily or permanently changes the destination of commands. Commands are strings, not interpreted by REXX itself but sent to an external environment.

18.4.1 VSE/ESA Environment

REXX/VSE provides the following host command environments:

∙

∙

∙

∙

∙

VSE for the REXX/VSE commands.

POWER for VSE/POWER spool-access service requests. JCL to issue JCL commands via a REXX program. CONSOLE lets you manage console sessions.

LINK and LINKPGM for linking to a program.

18.4.2 VM/ESA Environment

VM/ESA provides among others the following host command environments:

∙

∙

∙

∙

CMS implies full command resolution just as provided in usual interactive command (terminal) mode.

COMMAND implies basic CMS CMSCALL command resolution.

CPICOMM can be used to call program-to-program communications routines. OPENVM can be used to call OPENVM-type CSL routines, such as OpenEdition for VM/ESA callable services.

370VSE to OS/390 Migration Workbook