Entry and return

In an application program, you must identify the program entry point--the first program instruction to execute when the program gets control from AR/CTL. The program must also return control to AR/CTL. If the program already contains these structures for IMS, no changes are necessary.

At the entry point, the application program must define the list of program communication blocks (PCBs) it will access. The list of PCBs must be in the same order that the PCBs are coded in the PSB or application specification block (ASB). The checkpoint (I/O) PCB, if used, must be the first PCB in the list. Each AR/CTL call must access one of these PCBs to use for the call.

Use the PROCEDURE statement or the ENTRY statement as the entry point. The following example shows the use of the procedure statement:

PROCEDURE DIVISION USING CHKPPCB,ASAMPCB1,ASAMPCB2, ...

If you use the ENTRY statement, it must be the first executable statement in the procedure division. The ENTRY statement must list the names of the PCBs. The following example shows the use of the ENTRY statement:

ENTRY 'ANYNAME' USING CHKPPCB,ASAMPCB1,ASAMPCB2, ...

Use the GOBACK statement to return control to AR/CTL.

GOBACK

Entry and return

Comments