In this REXX version all the commands are executed via
command interpreter (normally COMMAND.COM)
So valid environments are:
A command is an expression, which may include function-calls, arithmetic operations, and so on. Operators or other special characters (for example, "(" or "*") must be specified in a string if they are to appear in the issued command.
Commands to environments COMMAND, SYSTEM may return its result to REXX stack when at the end of cmd appears the string (STACK, (FIFO or (LIFO (with the parenthesis).
If the string STACK> appears in the beginning of cmd, then stack is redirected to stdin of cmd.
Stack is flushed after redirecting it to stdin.
Redirection to or from STACK will create a temporary file with name like OAA.AAB that will be erased. It is nice to redirect all your temporary pipe files to a temporary directory. To do this set in your AUTOEXEC.BAT a new line containing:
where C:\TEMP is the temporary directory (which must exist) and you must have Read/Write authority. (Look also the function LOAD)