Using the CRTPGM Command

The Create Program (CRTPGM) command creates a program object from one or more previously created modules and, if required, one or more service programs. You can bind modules created by any of the ILE Create Module commands, CRTRPGMOD, CRTCMOD, CRTCBLMOD, or CRTCLMOD.

Before you create a program object using the CRTPGM command, you should:

1. Establish a program name.
2. Identify the module or modules, and if required, service programs you want to bind into a program object.
3. Identify the entry module.

   You indicate which module contains the program entry procedure through the ENTMOD parameter of CRTPGM. The default is ENTMOD(*FIRST), meaning that the module containing the first program entry procedure found in the list for the MODULE parameter is the entry module.

   Assuming you have only one module with a main procedure, that is, all modules but one have NOMAIN specified, you can accept the default (*FIRST). Alternatively, you can specify (*ONLY); this will provide a check that in fact only one module has a main procedure. For example, in both of the following situations you could specify ENTMOD(*ONLY).

   • You bind an RPG module to a C module without a main() function.
   • You bind two RPG modules, where one has NOMAIN on the control specification.
   Note:

   If you are binding more than one ILE RPG module with a main procedure, then you should specify the name of the module that you want to receive control when the program is called. You can also specify *FIRST if the module with a main procedure precedes any other modules with main procedures on the list specified for the MODULE parameter.
4. Identify the activation group that the program is to use.

   Specify the named activation group QILE if your program has no special requirements or if you are not sure which group to use. In general, it is a good idea to run an application in its own activation group. Therefore, you may want to name the activation group after the application.

   Note that the default activation group for CRTPGM is *NEW. This means that your program will run in its own activation group, and the activation group will terminate when the program does. Whether or not you set on LR, your program will have a fresh copy of its data the next time you call it. For more information on activation groups see Specifying an Activation Group.

To create a program object using the CRTPGM command, perform the following steps:

1. Enter the CRTPGM command.
2. Enter the appropriate values for the command parameter.

Table 32 lists the CRTPGM command parameters and their default values. For a full description of the CRTPGM command and its parameters, refer to the CL and APIs section of the Programming category in the i5/OS Information Center at this Web site - http://www.ibm.com/systems/i/infocenter/.

Once you have entered the CRTPGM command, the system performs the following actions:

1. Copies listed modules into what will become the program object, and links any service programs to the program object.
2. Identifies the module containing the program entry procedure, and locates the first import in this module.
3. Checks the modules in the order in which they are listed, and matches the first import with a module export.
4. Returns to the first module, and locates the next import.
5. Resolves all imports in the first module.
6. Continues to the next module, and resolves all imports.
7. Resolves all imports in each subsequent module until all of the imports have been resolved.
8. If any imports cannot be resolved with an export, the binding process terminates without creating a program object.
9. Once all the imports have been resolved, the binding process completes and the program object is created.