z/OS V1R6.0 DFSMS Access Method Services for Catalogs

ALLOCATE||||||||||||||When you allocate new SMS-managed data sets, you can let the ACSroutines select the volume for you. The ACS routines assign your data setto a storage class containing attributes such as VOLUME and UNIT. Youcan allocate your data set to a specific volume only if your storageadministrator has stated GUARANTEED SPACE=YES in the storage classassigned to your data set. The volume serial numbers you provide mightthen override the volume serial numbers used by SMS. If space is notavailable on the given volume, however, your request is not successful.Abbreviation: VOLVSEQ(vol-seq-no.)This locates which volume (1-255) of a multivolume begins data setprocessing. This parameter corresponds to the volume sequence number onthe VOLUME parameter in JCL. Use VSEQ only when the data set is acataloged data set.ALLOCATE ExamplesThe following scenarios use the ALLOCATE command to perform variousfunctions:Allocate a Data Set Using SMS Class Specifications: Example1In this example, the ALLOCATE command is used to allocate a new data set. Byproviding the SMS data class, management class, and storage class, you can takeadvantage of the attributes assigned by your storage administrator through theACS routines.Although this example includes DYNAMNBR, it is not required in this example.Because this example contains two DD statements, you can do up to twoallocations. DYNAMNBR is required only when the number of allocations exceedsthe number of DD statements. This example sets DYNAMNBR to 1. This allows upto three allocations for each DD statement (2) plus DYNAMNBR (1).//ALLOC JOB ...EC PGM=IDCAMS,DYNAMNBR=1//SYSPRINT DD SYSOUT=A//SYSIN DD *ALLOC -DSNAME(ALX.ALLOCATE.EXAMP1) -NEW CATALOG -DATACLAS(STANDARD) -STORCLAS(FAST) -MGMTCLAS(VSAM)/*Because the system syntax checks and ignores SMS classes when SMS is inactive,and because no overriding attributes are given, this example works only if SMS isactive. The parameters are:vvvvDSNAME states that the name of the data set being allocated isALX.ALLOCATE.EXAMP1.NEW creates a data set.CATALOG retains the data set by the system in the catalog after steptermination. This is mandatory for SMS-managed data sets.DATACLAS gives an installation-defined name of a data class to be assigned tothis new data set. The data set assumes the RECORG or RECFM, LRECL,KEYLEN, KEYOFF, AVGREC, SPACE, EXPDT or RETPD, VOLUME, CISIZE,48 z/OS V1R6.0 DFSMS Access Method Services for Catalogs