Beginning with SAS 9.2, SAS uses the IBM Large Block Interface by default whenever possible when reading an external file. This might cause an error when you read the same file twice with different block sizes.

For example, if, during the same SAS session, you read both the directory of a partitioned data set (PDS) or an extended PDS (PDSE) and a member of that PDS or PDSE using the same fileref or DD name, you might receive the following error:

To read the directory of a PDS or PDSE, you allocate the file using only the data set name (no member name). Typically, the INFILE statement has explicit attributes of RECFM=U, LRECL=256, and BLKSIZE=256. To subsequently process a member using the same fileref, you would use aggregate syntax (for example, fileref(member)). In previous releases, SAS processed the member correctly, but when using the Large Block Interface, SAS does not reset the BLKSIZE attribute for reading the PDS member. It retains the value of 256 set in the preceding DATA step that read the directory.

To circumvent this error, disable use of the Large Block Interface by specifying the SAS system option NOFILELBI before reading the directory of the PDS or PDSE.

Operating System and Release Information