The RERUN clause specifies that checkpoint records are to be taken. Subject to the restrictions given with each phrase, more than one RERUN clause can be specified.
For information regarding the checkpoint data set definition and the checkpoint method required for complete compliance to Standard COBOL 85, see the Enterprise COBOL Programming Guide.
Do not use the RERUN clause:
VSAM and QSAM considerations:
The file named in the RERUN clause must be a file defined in the same program as the I-O-CONTROL paragraph, even if the file is defined as GLOBAL.
For QSAM files, assignment-name-1 has the format:
Format: assignment-name for QSAM files >>-+--------+--+----+--name------------------------------------>< '-label--' '-S--'
The QSAM file must reside on a tape or direct access device. See also ASCII considerations.
SORT/MERGE considerations:
When the RERUN clause is specified in the I-O-CONTROL paragraph, checkpoint records are written at logical intervals determined by the sort/merge program during execution of each SORT or MERGE statement in the program. When the RERUN clause is omitted, checkpoint records are not written.
There can be only one SORT/MERGE I-O-CONTROL paragraph in a program, and it cannot be specified in contained programs. It will have a global effect on all SORT and MERGE statements in the program unit.
When multiple integer-1 RECORDS phrases are specified, no two of them can specify the same value for file-name-1.
If you specify the integer-1 RECORDS phrase, you must specify assignment-name-1.
When multiple END OF REEL/UNIT phrases are specified, no two of them can specify the same value for file-name-1.
The END OF REEL/UNIT phrase can be specified only if file-name-1 is a sequentially organized file.