Design of application programs that process double-byte data

 

There are certain considerations when designing application programs that process double-byte data, as discussed in this topic. Design your application programs for processing double-byte data in the same way you design application programs for processing alphanumeric data, with the following additional considerations:

• Identify double-byte data used in the database files.

• Design display and printer formats that can be used with double-byte data.

• If needed, provide DBCS conversion as a means of entering double-byte data for interactive applications. Use the DDS keyword for DBCS conversion (IGCCNV) to specify DBCS conversion in display files. Because DBCS workstations provide a variety of double-byte data entry methods, you are not required to use the i5/OS^® DBCS conversion function to enter double-byte data.

• Create double-byte messages to be used by the program.

• Specify extended character processing so that the system prints and displays all double-byte data. See Extended double-byte characters for instructions.

• Determine whether additional double-byte characters need to be defined. User-defined characters can be defined and maintained using the character generator utility (CGU). Information about CGU can be found in the ADTS/400: Character Generator Utility book.

When you write application programs to process double-byte data, make sure that the double-byte data is always processed in a double-byte unit and do not split a double-byte character.

 

Parent topic:

Application program considerations for DBCS