The SORTOU00 DD statement is required for every MAXSORT application in which the intermediate output is stored on tape.
The SORTOU00 DD statement defines the unit to be used for the output of the individual sorts and intermediate merges. MAXSORT will create and name these data sets which will eventually be merged to produce the final sorted output.
The data set names generated will have one of the two formats. If the TIMESTMP option is not specified (the installation default), data set names will have the format:
If the TIMESMP option is specified at installation time, data set names will have the format:
In either case, the S or M indicates whether the output is from the sort phase or from the merge phase; nn is the relative number of the data set (01 to 99). The Ddddhhmm time stamp refers to the time (Julian day, hour and minute) the sort began. The prefix default (TDS.) can be changed by specifying the BKPTDSN PARM option.
The following rules should be observed in coding the SORTOU00 DD statement:
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Specify DISP=(NEW,KEEP) and a permanent DSNAME and VOL=PRIVATE so that a scratch tape is used and the volumes are unloaded. Failure to specify this can result in the rewinding of the scratch tape and overwriting of the intermediate sort output.
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Specify the DEFER option in the UNIT parameter so that mount messages to the operator that do not pertain to MAXSORT are suppressed.
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SORTOU00 and SORTIN cannot share the same tape unit. However, SORTOU00 and SORTOUT may share the same tape unit unless the DYNATAPE PARM is specified. SORTIN and SORTOUT may always share the same unit.
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If DYNATAPE is in effect, the tape unit name must be the same as the unit name specified in the TAPENAME PARM.