You want to select only those data items whose name contains the characters 'RL' in the third and fourth character positions. The other characters in the name can be any character. You must provide the following values for the NAME and NAMEMASK keywords:

          IXLCACHE …,NAME=DNAME,NAMEMASK=MASK,…
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DNAME     DC   CL16'XXRL'
MASK      DC   BL2'0011000000000000'
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