DB2 Server for VSE & VM: Application Programming

Link-Editing and Loading the Program

After compilation, programs must be link-edited and loaded before they can be run.

Link-Editing the Program with Supplementary Information

Including Relocatable Modules

To allow your program to communicate with the database manager, you must link-edit your program with one or more DB2 Server for VSE relocatable modules. One of these relocatable modules is called the resource adapter stub. Every DB2 Server for VSE application program must be link-edited with this stub. FORTRAN and COBOL programs need to be link-edited with additional relocatable modules. Also, depending on the nature of your program, you may have to link-edit with others. For instance, when link-editing a module that uses CICS/VSE, you may have to INCLUDE a CICS/VSE module immediately following the PHASE system control statement and before the EXEC ASSEMBLY system control statement. Whether you INCLUDE this module depends on your host language.

When you load your program, the VSE linkage editor automatically links your program to all modules that you included. The linkage editor also resolves virtual storage addresses between files.

Including CICS/VSE Procedures

When link-editing a module that uses CICS/VSE, you should include the following procedures for your application:

• For all assembler applications, you must have an INCLUDE for CICS/VSE module DFHEAI immediately following the PHASE system control statement and before the EXEC ASSEMBLY system control statement. DFHEAI must be the phase entry point.
• For all C applications, you must have an INCLUDE for CICS/VSE module DFHELII. This module must be the phase entry point.
• For all COBOL applications, you must have an INCLUDE for CICS/VSE module DFHECI immediately following the PHASE system control statement and before the EXEC IGYCRCTL (EXEC FCOBOL in OS/VS COBOL) system control statement. DFHECI must be the phase entry point.
• For all PL/I applications, you must have an INCLUDE for CICS/VSE module DFHPL1I immediately following the PHASE system control statement and before the EXEC PLIOPT (EXEC IEL1AA in IBM PL/I for VSE) system control statement. DFHPL1I must be the phase entry point.

See Figure 53 for an example of these procedures.

Including Extra Linkage Modules

When link-editing any DB2 Server for VSE application, you must include some extra linkage modules following the application program module that uses the database manager. Use these extra modules as indicated below:

• For all batch and ICCF applications, you must include the linkage module ARIPRDID.

• For all online (CICS/VSE) applications, you must include the linkage module ARIRRTED.

In addition to the modules listed above, some of these may be required:

• For all programs written in COBOL (regardless of whether they are batch, ICCF, or online), you must also include the module ARIPADR4. Include ARIPADR if your program was preprocessed prior to SQL/DS Version 2 Release 2. (You need not include it if VSE autolink is used.)

  Note:

  If you use a COBOL SORT in your program, include ARIPADR4 (or ARIPADR) and ARIPRDID (or ARIRRTED) before the compile step.

• For all programs written in FORTRAN, you must also include the modules ARIPEIFA and ARIPSTR. If the FORTRAN program uses the module ARISSMF, this file must also be included. See the discussion of the SQLCA in Chapter 6, Testing and Debugging.

• For all programs that will include the DBS utility (regardless of whether they are batch, ICCF, or online), you must also include the modules ARISYSDD, ARIDSQLA, and ARIDDFP.
• All programs (except FORTRAN programs) that use the module ARISSMA, must also link-edit this module. See the discussion of the SQLCA in Chapter 6, Testing and Debugging for further information.

If you receive an unresolved external reference message for a module name that begins with ARI or SQL, check the link process to ensure that all required extra linkage modules are included.

Some of these modules contain entry points with names that are different from the module name. The code generated by the DB2 Server for VSE preprocessor can reference one of these entry points, depending on the SQL statements in your application.