The LABEL statement indicates that the data statements (called label data statements) are to be treated as user labels. These new user labels are placed on the output data set. The next control statement indicates to IEBUPDTE that the last label data statement of the group has been read.

The syntax of the LABEL statement is:

There can be no more than two LABEL statements per execution of IEBUPDTE. There can be no more than eight label data statements following any LABEL statement. The first 4 bytes of each 80-byte label data statement must contain "UHLn" or "UTLn", where n is 1 through 8, for input header or input trailer labels respectively, to conform to IBM standards for user labels. Otherwise, data management will overlay the data with the proper four characters.

When IEBUPDTE encounters a LABEL statement, it reads up to eight data statements and saves them for processing by user output label routines. If there are no such routines, the saved records are written by OPEN or CLOSE as user labels on the output data set. If there are user output label processing routines, IEBUPDTE passes a parameter list to the output label routines. The label buffer contains a label data record which the user routine can process before the record is written as a label. If the user routine specifies (via return codes to IEBUPDTE) more entries than there are label data records, the label buffer will contain meaningless information for the remaining entries to the user routine.

When UPDATE=INPLACE is specified in a CHANGE statement, user input header labels can be updated by user routines, but input trailer and output labels cannot be updated by user routines. User labels cannot be added or deleted. User input header labels are made available to user routines by the label buffer address in the parameter list. The return codes when CHANGE UPDATE=INPLACE is used differ slightly from the standard return codes.

If you want to examine the replaced labels from the old master data set, you must:

1. Specify an update of the old master by coding the UPDATE=INPLACE parameter in a function statement.
2. Include a LABEL statement in the input data set for either header or trailer labels.
3. Specify a corresponding user label routine.

If these conditions are met, fourth and fifth parameter words will be added to the standard parameter list. The fourth parameter word is not now used; the fifth contains a pointer to the replaced label from the old master. In this case, the number of labels supplied in the SYSIN data set must not exceed the number of labels on the old master data set. If you specify, via return codes, more entries to the user's header label routine than there are labels in the input stream, the first parameter will point to the current header label on the old master data set for the remaining entries. In this case, the fifth parameter is meaningless.