• —RPG/400 is a programming language designed to make it easier to create business software

• —A language under evolution

• —Used for development of Batch and On-line programs

• —Is a fixed format (position dependent) language, unlike C, specifications need to be entered into specific columns - SEU prompts for entering these specifications

 

—Valid character set consists of

• —Letters A-Z

• —Numbers 0-9

• —Characters + - * , . ‘ & / $ # : @

• —Blank character

 

Directives

• —Compiler directive statements /TITLE, /EJECT, /SPACE, and /COPY

• —Allow a programmer to

—        specify heading information to appear at top of each page of compiler listing 

—        indicate that subsequent specifications are to begin on a new page of compiler listing

—        control line spacing within compiler listing, and

—        insert records from other file members during a compile, at the point where the /COPY      occurs

• —/TITLE (Positions 7-12)

• —/EJECT (Positions 7-12)

• —/SPACE (Positions 7-12)

• —/COPY (Positions 7-11)—

 Note : For complete syntax refer RPG/400 Reference

 

Symbolic Names

• —A name that uniquely identifies a specific entity in a program

• —Common rules, exceptions may occur for different symbolic names

• —First character of the name must alphabetic, including $, #, and @, remaining can be any listed in the character set and must be left-adjusted

• —Blanks can fill out the entry but not to be embedded in the name

• —Cannot be a RPG/400 reserve word

• —Can be 1-6 characters long, and must be unique

 

Symbolic names can be assigned to entities as

 

• —Arrays

• —Constants

• —Data Structure

• —EXCPTs (exception output records)

• —Fields

• —Files

• —Subroutines

• —Tables

• —KLISTs (key field lists)

• —Labels

• —Named constants

• —PLISTs (parameter lists)

• —Record names

• —Subfields