Writing a PLTPI program to start the connection

We can write your own PLTPI program, based on the supplied assembler sample thlqual.SCSQASMS(CSQCSPLT).

Although this sample is written in assembler, we can write your own program in any language supported by CICS. A typical use of PLTPI programs is for overriding the INITPARM settings if your CICS adapter initiation queue name is too long. (We cannot use more than 42 characters for an initiation queue name in an INITPARM statement.) If your PLTPI program gets its input parameters from a data set, you do not need an INITPARM statement.

Your PLTPI program must link to the adapter connect program, thlqual.SCSQCICS(CSQCQCON), and pass a parameter list that specifies the connection values to be used. The parameter list is described in the WebSphere MQ for z/OS System Administration Guide. Figure 12 shows the LINK command that your PLTPI program must issue. In this example, the parameter list is named CONNPL. Because no terminals are available at this stage of CICS start up, use the COMMAREA option to pass the parameter list.

Figure 12. Linking to the adapter connect program, CSQCQCON, from a PLT program. The COMMAREA option is used, because no terminals are currently available.

EXEC CICS LINK PROGRAM('CSQCQCON')
          COMMAREA(CONNPL) LENGTH(length of CONNPL)

For more information about writing CICS PLTPI programs, see the CICS Customization Guide.