Common Address Space Shell (CASRV) › Customize a Common Address Space Shell

Customize a Common Address Space Shell

Because a Common Address Space Shell (CASRV) must support execution in early IPL environments, no explicit dependency exists in the following areas:

• JCL PROC
• STEPLIB
• Externally allocated parameter data set.

The CASRV uses the CA Common Service PARMLIB reader service. Therefore, command statements can be obtained through the z/OS system logical PARMLIB data sets, or through an externally allocated data set. Furthermore, internal commands can be passed when the address space is created as previously described.

The CASRV control program commands provide the basis for customizing its environment and the server application that executes within it. CASRV does not support any explicit initialization statements. But the commands that are passed as internal commands to an address space create, and any commands read from an external data set, effectively function as initialization statements.

Many of the CASRV control program commands serve to customize the address space for a server application. To some degree, the CASRV functions as a z/OS INITIATOR because it lets you allocate resources for a hosted server application before attaching the server application. By including the appropriate CASRV control program commands in an internal source or in an external data set or PARMLIB member, data sets can be allocated, message tables can be established, and then server applications can be started in a CASRV.