An IBM-i Service Program is a collection of reusable procedures and data items that can be accessed by other Integrated Language Environment (ILE) programs or service programs on the IBM i (AS400/iSERIES) system.
Here are some key points about service programs:
Here's a simple example of creating a service program:
// Module with procedures
DCL-PROC AddNumbers;
DCL-PI *N INT(10);
NUM1 INT(10);
NUM2 INT(10);
END-PI;
RETURN NUM1 + NUM2;
END-PROC;
DCL-PROC SubtractNumbers;
DCL-PI *N INT(10);
NUM1 INT(10);
NUM2 INT(10);
END-PI;
RETURN NUM1 - NUM2;
END-PROC;
DCL-PROC AddNumbers;
DCL-PI *N INT(10);
NUM1 INT(10);
NUM2 INT(10);
END-PI;
RETURN NUM1 + NUM2;
END-PROC;
DCL-PROC SubtractNumbers;
DCL-PI *N INT(10);
NUM1 INT(10);
NUM2 INT(10);
END-PI;
RETURN NUM1 - NUM2;
END-PROC;
We would create this using the CRTSRVPGM command:
// Create the service program
CRTSRVPGM SRVPGM(MYLIB/MYSRVPGM) MODULE(MYLIB/MYMODULE) EXPORT(*ALL)
CRTSRVPGM SRVPGM(MYLIB/MYSRVPGM) MODULE(MYLIB/MYMODULE) EXPORT(*ALL)
In this example, 'AddNumbers' and 'SubtractNumbers' are procedures within a module that are included in a service program. The 'CRTSRVPGM' command creates the service program and specifies that all procedures in the module should be exported.