FILL=NULL specification

Specify FILL=NULL on the DPAGE or MSG statement and specify the OFTAB= parameter in the DIV or DPAGE statement to preserve field separation. If FILL=NULL is specified on the DPAGE or MSG statement and the OFTAB= parameter is not present on the DIV statement or the DPAGE statement, a compressed output data stream is produced and field separation is not evident.

Use FILL=NULL for graphic data. If GRAPHIC=NO and FILL=NULL are specified in the SEG statement, any X'3F' in the non-graphic data stream is compressed out of the segment and undesirable results can be produced. Send non-graphic data on output as fixed length output fields and do not specify FILL=NULL.

Output message segments and message fields defined for each segment are processed sequentially by MFS if option 1 or 2 is defined in the OPT= operand of the MSG statement. Message fields in option 1 and 2 segments are defined as fixed-length fields and in fixed position. The data for these fields can be supplied as fixed-length fields, or it can be shortened by the application program. The data can be shortened by two methods:

• By inserting a short segment if no data exists for fields defined at the end of a segment.
• By placing a null character (X'3F') in the field. MFS scans segment data left to right for a null character. The first null character encountered terminates the data for a corresponding MFLD. Positioning of all fields in the segment remains the same as the positioning of defined fields regardless of null characters.