Header records

The first two records of an IEBCOPY unload data set contain information that is required to load the data set. The first record (COPYR1) contains a status field, an ID field, and a DCB information field. The status and ID fields are used for validity checking procedures. The DCB field is used to initialize the output data set during a load function. The second record (COPYR2) contains parts of the original data extent block (DEB) of the unloaded partitioned data set. When the data set is to be loaded, this information is used to update all the user and note list TTRs. Table 1 and Table 2 show the different fields in the COPYR1 and COPYR2records.

Table 1. Contents of the COPYR1 descriptor record
Offset Into Record	Field size (Bytes)	Type Of Data	Field Contents
0	64	Structure	COPYR1 - first header record
0	4	Structure	Block Descriptor Word (BDW) for RECFM=VS data sets
0	2	Unsigned Binary	Length of block, including BDW
2	2	reserved	Must be zero
4	4	Structure	Segment Descriptor Word (SDW) for RECFM=VS data sets
4	2	Unsigned Binary	Length of segment, including SDW
6	2	Bit Flags	Must be zero (COPYR1 record is never segmented)
8	1	Bit Flags	Unload Data set Information. Numbering the MSB as "0",
			0 & 1 - B'00' = valid unload data set in old format.
			B'01' = valid unload data set in PDSE format.
			B'10' = the original data set cannot be reloaded because this unload data set is known to be incomplete or in error.
			B'11' = Reserved format.
			2 - Reserved, and must be zero.
			4 - When set, the original data set was known to contain program objects. When not set, it is not known if the contents are or are not programs.
			4 - Reserved, and must be zero.
			5 - Reserved, and must be zero.
			6 - Reserved, and must be zero.
			7 - When set, the original data set was a PDSE.
9	3	Binary	The constant value X'CA6D0F'.
			(The following fields are from the original data set label (Format 1 DSCB).)
12	2	Bitstring	Data set organization (DS1DSORG). X'0200' is PDS.
14	2	Unsigned Binary	Block size (DS1BLKL)
16	2	Unsigned Binary	Logical Record Length (DS1LRECL)
18	1	Bit Flags	Record Format (DS1RECFM) Numbering the MSB as "0",
			0 & 1 - B'00' is unknown format
			B'01' is Variable format (RECFM=V)
			B'10' is Fixed format (RECFM=F)
			B'11' is Undefined (RECFM=U)
			2 - When set, DASD track overflow may be used.
			3 - When set, records may be blocked.
			4 - When set, variable format records may be spanned; for fixed format only the last block may be short.
			5 & 6 - B'00' is first record byte is a data byte.
			B'01' first byte is ANSI/ISO carriage control.
			B'10' first byte IBM machine carriage control.
			B'11' is an invalid combination.
			7 - Reserved and may be either zero or one.
19	1	Unsigned Binary	Length of record key field (DS1KEYL)
20	1	Bit Flags	Option codes associated with the data set (DS1OPTCD)
21	1	Bit Flags	SMS Indicators (DS1SMSFG). Numbering the MSB as "0",
			0 - Managed data set
			1 - unpredictable
			2 - Data set is reblockable
			3 - unpredictable
			4 - Data set is a PDSE
			5 - unpredictable
			6 - Reserved
			7 - Reserved, and must be zero. (End of fields from the original data set label).
22	2	Unsigned Binary	The block size of this container data set, which contains the unload data set.
24	20	Structure	Information about the device from which the data set was unloaded. Obtained by a DEVTYPE macro with the DEVTAB parameter. ¹
44	2	Unsigned Binary	Number of header records. Zero implies 2.
46	18	reserved	Zeros in "old" format unload data set (The following fields are from the original data set label (Format 1 DSCB).)
46	1	reserved	Must be zero
47	3	Structure	Date last referenced yydddd (DS1REFD)
50	3	Structure	Secondary Space Extension (DS1SCEXT)
53	4	Structure	Secondary Allocation (DS1SCALO)
57	3	Structure	Last Track Used TTR (DS1LSTAR)
60	2	Unsigned Binary	Last Track Balance (DS1TRBAL)
62	2	reserved	Must be zero (End of fields from the original data set label).
Notes: These fields are highly device dependent and are required to translate absolute DASD addresses (MBBCCHHR) in the member data records to relative addresses (TTR). The DEB control block and DEVTYPE macro are documented in z/OS DFSMSdfp Advanced Services

Table 2. Contents of the COPYR2 descriptor record
Offset Into Record	Field size (Bytes)	Type Of Data	Field Contents
0	284	Structure	COPYR2 - first header record
0	4	Structure	Block Descriptor Word (BDW) for RECFM=VS data sets
0	2	Unsigned Binary	Length of block, including BDW
2	2	reserved	Must be zero
4	4	Structure	Segment Descriptor Word (SDW) for RECFM=VS data sets
4	2	Unsigned Binary	Length of segment, including SDW
6	2	Bit Flags	Must be zero (COPYR2 record is never segmented.)
8	16	Structure	Last 16 bytes of basic section of the Data Extent Block (DEB) for the original data set. ¹
24	256	Structure	First 16 extent descriptions from the original DEB. ¹
280	4	reserved	Must be zero
Notes: These fields are highly device dependent and are required to translate absolute DASD addresses (MBBCCHHR) in the member data records to relative addresses (TTR). The DEB control block is documented in z/OS DFSMSdfp Advanced Services. DEVTAB information is documented inDFP System Data Administration.