RPG LIMITATIONS

Like all high-level languages, RPG has a set of restrictions. RPG IV has fewer limitations than previous versions of RPG. The features listed in Table 1.4 document any significant RPG language restrictions, along with several previous limitations that have been removed in RPG IV. These are marked "No limit."

Table 1.4: RPG IV Limitations

Feature	Limit
AN/OR (positions 7 to 8 of Calc spec)	No limit
Array elements	32,767 per array/table
Arrays and tables	No limit
Compile-time array or table length	100 positions
Data structure length	65,535 positions for named data structures 9,999,999 for unnamed data structures
Data structure occurrences	32,767 per data structure
Edit word length	Literal: 24 positions Named Const: 115 positions
Field length	Char: 65,535 positions; Numeric: (31, 30)
Field name	4,096 characters
Files (open files per program)	No limit (actually 32767)
File key length	2,000 positions
Lines per page (program-described)	Minimum of 2; maximum of 255
Lines per page (externally described)	Minimum of 1; maximum of 255
Matched fields (combined length)	256 positions
Named constants	Char: 1024 positions; Numeric: (31, 30)
Nested IF, DOxxx, SELECT, FOR groups	100 levels
Parameters	255 program to program; 399 to procedures
Primary files	1 per program
Printer files	No limit (8 standard overflow indicators available)
Program Status Data Structure	1 per program
Record address files (ADDROUT)	1 per program
Record format length	99,999 positions (system limit is)
Spacing and skipping printed output	0 to 255 lines
Subroutines	32,767 per program