Use SAS Enterprise Guide to add a prompt to your project, and then add the prompt to the node. Test the operation in Enterprise Guide and when you have it working, create a stored process from the node. The prompt will then be available in your stored process.
A lot has been written about prompts; here is some documentation to get you started:
SAS Enterprise Guide 8.1: User's Guide > Working with Prompts > About Prompts https://go.documentation.sas.com/?cdcId=egdoccdc&cdcVersion=8.1&docsetId=egug&docsetTarget=n1ufxermnvwsbbn1tvu68m9r6uw1.htm
Vince DelGobbo
SAS R&D
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