When you specify different parameter values for SFLPAG keyword and SFLSIZ, the SFLSIZ value specifies the number of records that can be placed into the subfile. If your program places a record with a relative record number larger than the SFLSIZ value into the subfile, the subfile is automatically extended to contain it (up to a maximum of 9999 records). The parameter value you specify should be large enough to accommodate the maximum number of records you would normally have in the subfile.
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