So in the file header we got: $EQU FH2$S_RECATTR 32 $EQU FH2$W_RECATTR 20 I assume the content of those 32 bytes are what is documented in IO Users Reference Manual as "ACP-QIO Record Attributes Area". Fine. But the ident area for ODS-5 record has: $EQU FI5$S_EX_RECATTR 8 $EQU FI5$Q_EX_RECATTR 52 What does those 8 bytes contain? Arne