When a UNIX file is found within a sequential concatenation, the system forces the use of the LRECL, RECFM, and BUFNO from the previous data set. (The unlike attributes bit is not set in a like sequential concatenation.) Also, the system uses the same NCP and BLKSIZE values as for any BSAM sequential like concatenation. For QSAM, the system uses the value of BLKSIZE for each data set. For the rules for concatenating like and unlike data sets, see Concatenating Data Sets Sequentially. Also the system might force the use of the LRECL from the previous data set unless overridden by the application on the UNIX files DD statement.

Restriction: You cannot use sequential concatenation (DSORG=PS in DCB) to read UNIX directories sequentially.