Support of Standard REXX Features

This section discusses the support of standard REXX features such as SAY and TRACE statements, PULL and PARSE EXTERNAL statements, REXX stacking, and REXX functions.

SAY and TRACE Statements

The REXX SAY and TRACE terminal I/O output statements use CICS Terminal Control support to provide simulated line-mode output. Also, the SET TERMOUT command can be used to route line-mode output into a temporary storage queue.

PULL and PARSE EXTERNAL Statements

The REXX PULL and PARSE EXTERNAL terminal I/O input statements use CICS Terminal Control support to provide simulated line-mode input.

Notes:
  1. PULL (or PARSE PULL) first attempts to pull a line from the program stack and, only if it is empty, issues a read to the terminal.
  2. Attempting to perform terminal line-mode input from a REXX exec that is running as part of a non-terminal attached transaction, is an error, which causes the exec to terminate with an error message.

REXX Stack Support

Each user has a shared program stack between multiple generations of REXX execs. This single automatic program stack is not named. If named program stacks are desired, use the RLS LPUSH, LQUEUE, and LPULL commands.

REXX Function Support

REXX/CICS supports the standard SAA Level 2 built-in function set, with the following exceptions: