When a log stream copy (DWWLC) is performed, the records in the MVS™ log stream are copied to a sequential data set. In addition to the records in the MVS log stream, DWWLC writes two additional records to the output file, the first record and the last record, both called LOGI records.
The layout of the LOGI record is as follows:
1 LOGI
2 LOGITYPE CHAR(4) , /* >DWW */
2 LOGIVERS FIXED(31), /* 0001 */
2 * CHAR(8) , /* RESERVED */
2 LOGIBLKID CHAR(8) , /* BLOCKID */
2 * CHAR(8) , /* RESERVED */
2 LOGITIME , /* TIME BLOCK */
3 LOGIGMT CHAR(8) , /* TIME BLOCK WRITTEN GMT TOD*/
3 LOGILOCAL CHAR(8) , /* TIME BLOCK WRITTEN LOCAL TOD*/
2 * CHAR(8) , /* RESERVED */
2 LOGINAME CHAR(26) , /* MVS LOG NAME */
2 * CHAR(6) , /* RESERVED */
2 * CHAR(16) ; /* RESERVED */
Use a precopy exit if you want to examine the records before they are written to the output data set.