Each logical record (except with VSAM), in all record formats, can contain an optional control character. This control character controls stacker selection on a card punch or card read punch, or printer spacing and skipping. If a record containing an optional control character is directed to any other device, it is considered to be the first data byte, and it does not cause a control function to occur.
In format-F and format-U records, the optional control character must be in the first byte of the logical record. In format-V or format-D records, the optional control character must be in the fifth byte of the logical record, immediately following the record descriptor word of the record.
Two control character options are available: machine code and extended code defined by ANSI. Code the control character in the RECFM parameter of the DCB macro. If either option is specified in the data control block, you must include a control character in each record. Other spacing or stacker selection options also specified in the data control block are ignored.
Independently of control characters, each record can contain a table reference character. If each record contains a control character and a table reference character, the control character is first.