The system restart routine retrieves the information recorded in a checkpoint record, restores the contents of main storage and all registers, and restarts the program.
You can begin the restart routine in one of two ways:
- Automatically at the time an interruption stopped the program
- At a later time as a deferred restart
of the job control language determines the type of restart. You can
RD parameter on either the
EXEC statement. If coded on the
the parameter overrides any
RD parameters on the
suppress both restart and writing checkpoints, code
an error message is issued and the restart is canceled. Only checkpoints
taken by DFSORT are valid.
Data sets that have the
SYSOUT parameter coded
DD statements are handled in various ways
depending on the type of restart.
If the checkpoint data set
is multivolume, include in the
VOLUME parameter the
sequence number of the volume on which the checkpoint entry was written.
If the checkpoint data set is on a 7-track tape with nonstandard labels
or no labels, the
SYSCHK DD statement must contain