SYSIN2 DD statement

When using SYSIN2:

• The SYSIN DD data set is the primary input. DFSDDLT0 attempts to insert the SYSIN2 control statements into the SYSIN DD data set.
• You must code the control groups and sequence numbers properly in columns 73 to 80 or the merging process will not work.
• Columns 73 and 74 indicate the control group of the statement.
• Columns 75 to 80 indicate the sequence number of the statement.
• Sequence numbers must be in numeric order within their control group.
• Control groups in SYSIN2 must match the SYSIN control groups, although SYSIN2 does not have to use all the control groups used in SYSIN. DFSDDLT0 does not require that control groups be in numerical order, but the control groups in SYSIN2 must be in the same order as those in SYSIN.
• When DFSDDLT0 matches a control group in SYSIN and SYSIN2, it processes the statements by sequence number. SYSIN2 statements falling before or after a SYSIN statement are merged accordingly.
• If the sequence number of a SYSIN2 statement matches the sequence number of a SYSIN statement in its control group, the SYSIN2 overrides the SYSIN.
• If the program reaches the end of SYSIN before it reaches the end of SYSIN2, it processes the records of SYSIN2 as if they were an extension of SYSIN.
• Replacement or merging occurs only during the current run. The original SYSIN data is not changed.
• During merge, if one of the control statements contains blanks in columns 73 through 80, DFSDDLT0 discards the statement containing blanks, sends a message to PRINTDD, and continues the merge until end-of-file is reached.