They can be, but it's the same principal. Store the results in a temp table for further processing. Nothing much fancier than that.
CREATE TABLE #StoredProcOutput (
<definition>
);
INSERT INTO #StoredProcOutput
EXEC SomeStoredProcedure
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability