Before coding your program

In addition to the information you need about the database processing that your program does, you need to know about message processing. Before you start to code, be sure you are not missing any of this information. Also, be aware of the standards at your installation that affect your program.

Information you need about your program's design:

  • The names of the logical terminals that your program will communicate with
  • The transaction codes, if any, for the application program's MPP skeleton to which your program will send messages
  • The DC call structure for your program
  • The destination for each output message that you send
  • The names of any alternate destinations to which your program sends messages

Information you need about input messages:

  • The size and layout of the input messages your program will receive (if possible)
  • The format in which your program will receive the input messages
  • The editing routine your program uses
  • The range of valid data in input messages
  • The type of data that input messages will contain
  • The maximum and minimum length of input message segments
  • The number of segments in a message

Information you need about output messages:

  • The format in which IMS expects to receive output from your application program MPP skeleton
  • The destination for the output messages
  • The maximum and minimum length of output message segments