How to pull console input with non-empty stack in REXX?

I want to ask for console input without disturbing the contents of the stack. However, the PULL function will always pull from the stack first if it is not empty. How can I do this?

Depending on the platform, you may be able to use PARSE EXTERNAL. Not every Rexx implementation supports it - it's not part of the ANSI standard. But, for example, IBM's TSO/E and z\VM implementations do. PARSE EXTERNAL always reads from the console, no matter what the contents of the stack.