This parameter tells VSAM whether you want to let two or more jobs to process your file at the same time. It specifies how a VSAM dataset can be shared
SHARE OPTIONS(cr value cs value)
cr value : Specifies the value for cross region sharing. Cross region sharing is defined as different jobs running on the same system using Global Resource Serialization(GRS), a resource control facility available only under MVS/XA and ESA
cs value : Specifies the value for cross system sharing means different jobs running on different system in a NONGRS environment
? multiple read OR single write
? multiple read AND single write
? multiple read AND multiple write
Default :- SHAREOPTIONS(1 3)
The REUSE parameter
The REUSE parameter specifies that the cluster can be opened a second time as a reusable cluster. NOREUSE is the default, and specifies the cluster as non-reusable.
Some application call for temporary dataset or workfile that must be created, used and deleted each time the application runs. To simplify these applications, VSAM lets you create reusable files. The reusable file is a standard VSAM KSDS, ESDS or RRDS. The only difference is that, if you open an existing reusable file for output processing, VSAM treats the file as if were empty. Any records already present in the file are ignored.