Introduction To RPG IV:

Overview:

This module enables the student to understand the concept of RPG IV.

Outline:

Topics covered,

a. Introduction to RPG IV

b. Built -in functions

c. Date and Time Data Types

Objective:

By the end of this module, the student should be able to:

a. Understanding Of Basic Concepts RPG IV

b. Built In Function

c. Date and Time Data Types

Introduction to RPG IV

RPG IV is the latest version of RPG language. RPG IV is a syntax that participates in IBM’s Integrated Language Environment (ILE) architecture or programming model. RPG IV diverges from its predecessor RPG III, in significant ways. This latest release is backward compatible. That means program written before 1995 can easily be converted to RPG IV and subsequently modified without complete program rewrite.

RPG III was criticized as difficult to understand because of its short data names, abbreviated operation codes and rigidly fixed format. The critics contended that the language was showing age in its limited choice of data types (e.g. no direct support date data types) and its inability to handle multidimensional arrays etc.

To address some of these shortcomings in RPG, IBM introduced in 1994, concurrent with the release of Version 3 Release of OS/400, improved version of RPG and named it RPG IV.

RPG IV relaxes many of the strict fixed format requirements imposed by previous RPG versions, allowing free-format expressions and keyword notation in its specifications. Data naming limits have been extended and many other artificial limits have been effectively removed from the language. RPG IV adds several new organizational concepts like a central data definition specification and procedure prototyping.

In 2000, IBM created a new all inclusive eServer family; the AS/400 became the eServer, iSeries 400 (iSeries in short). Recent release of RPG IV has focused on enabling the RPG IV architecture to co-exist with Internet-based applications and object-oriented languages like Java.

· Summary of RPG III to RPG IV Changes:

o A source migration tool is provided to convert RPG III source code to RPG IV source code. The default source-file name has changed from QRPGSRC to QRPGLESRC and the record length has been expanded from 92 to 112 bytes. The existing SEU date and sequence number fields remain unchanged. The increase of the source statement length from 80 to 100 characters accommodates the new syntax with longer file and field names as well as the expanded comment length (positions 81 to 100).

o The new Definition specifications. (P-spec) allow you to define sub-procedures. In RPG terms, sub-procedures are similar to sub-routines except:

§ You can pass parameters to them.

§ They do not use RPG cycle

§ They can be prototyped (which causes the compiler to check parameters for consistency).

§ They allow you to define local variables.

§ They can be invoked in expressions, similar to IBM supplied built-in functions.

§ You can call them outside the source module in which they are defined if they are exported.

· RPG IV now supports 10-character file, format, field, constant, data structure, key-list, subroutine label and other symbolic names.

· The underscore(_) is now valid in symbolic name but it cannot be the first character. Thus EMP_NAME is a valid field name but _NAME is not.

· Array subscripts are specified using parentheses () instead of a comma’,’.

ARR,X in RPG III becomes ARR(X) in RPG IV.

o Uppercase and lowercase characters can be used anywhere in an ILE RPG program. The field names EmpName and EmpLoc are now valid. The operation codes ‘CHAIN’, ‘Chain’ all perform the same function. The (ILE RPG compiler converts the lowercase characters to uppercase. Comments, literals (with the exception of hexadecimal literals), compile time array and table data are not translated to uppercase. Currency symbol ($), date and time-edit values on the Control specifications (H-spec), date and time separator characters on the Input specification (I-spec) and comparison characters on Record Identification entries on I-spec are also not converted to uppercase.

o Blank lines are permitted in RPG IV. Source statements that are blank in positions 6 to 80 are treated as comments. An asterisk (*) in position 7 also forces a statement to be a comment just as it does in RPG III. In general, positions 81 to 100 are treated as comments in source statements except for compile-time table and array data.

o Freeform mathematical expressions and logical expressions are available. With the EVAL operation you area now able to use natural mathematical expressions as follows:

EVAL SLSTOT=SLSAMT1+SLSAMT2

o Built-in functions are similar to operation codes as they perform operation on given data. However, built-in functions can be embedded into an expression. E.g.

EVAL LSTNAME=%SUBST(FULLNAME:16:20)

o With newer V4R2 built-in functions, you can eliminate resulting indicators on operation such as CHAIN, SETALL or LOOKUP. E.g. you can use the %FOUND function determine if a CHAIN was successful as shown in following statement:

CUST# CHAIN CUSTREC

IF %FOUND(CUSTMST)

o Now you have more powerful date manipulation capabilities through date, time and time-stamp data type support including new date and time operation such as Add Duration (ADDDUR) and Subtract Duration (SUBDUR).

o Many operation code names such as LOKUP, DELET, UPDAT, UNLCK and REDPE have been changed to longer and more meaningful names as LOOKUP, DELETE, UPDATE, UNLOCK and READPE.

Comparison between RPG III and RPG IV.

Sr.No	RPG III	RPG IV
1.	Compilation of source members creates an executable object called PGM using command CRTXXXPGM (where XXX is a program type) RPG III Compile PGM E.g. CRTRPGPGM: RPG program object. CRTCLPGM: CL program object	Compilation of source member, first creates a non-executable object MODULE using command CRTXXXMOD. (Where XXX is a program type). Various modules are bound together to create program object PGM using command CRTPGM. (It is not any particular type of program, just *PGM).
2.	RPG III provides dynamic calls. (Call to external programs are resolved at run time)	RPG IV provides static (Compile time) as well as dynamic (run-time) call.
3.	RPG III supports OPM debugger.	RPG IV supports source-level debugger.
4.	Record Length of the source code=92	Record Length of the source code =112
5	Field names are restricted up to 6 chars.	RPG IV supports 10-character field length.
6.	Constants can be defined up to 256 bytes	Constants can be defined up to 1024 bytes.
7.	Decimal places up to 9 digits	Decimal places up to 30 digits
8	Character variables and array elements are restricted up to 256 bytes	Character variables and array elements are of 32767 bytes
9	Maximum 50 files can be opened.	No limits.
10	Length of Factor 1 and Factor 2=10	Length of Factor 1 and Factor 2=14
11	Opcode length =5	Opcode length =10
12	Fixed format	Free Format only for Factor 2
13	Indicators are compulsory	Not compulsory
14	Variables scope is limited to program only. No concept of Local Variable	Introduces a concept of Local Variables

▪ Introduction to RPG IV specifications in brief

RPG IV programs are written as fixed-format or free-format specifications. Different specification forms convey different kinds of information to the RPG IV compiler, which translates the program into machine language.

The E specs in RPG III have been removed in RPG IV. The E specs and I specs together are defined by new D specifications. A P spec is one more specs introduced in RPG IV.

7 Specifications

Specification Name	Identifier in 6^th position
Header Specifications	H
File Description Specifications	F
Definition Specifications	D
Input Specifications (for program described input files)	I
Calculation Specification	C
Procedure Specification	P
Output Specifications	O

▪ Specifications in detail

H Specification

In ILE RPG III, Header specification is used for writing header information in a program. However, instead of entering values in specific positions (Fixed-format), as in RPG III, ILE RPG uses keywords notations. Many Compile options can be specified through Keywords in H specs. Positions 7 through 80 are used for entering control specification keywords.

o DATFMT (Date Format): DATEFMT specifies the format of date literals and date fields within the program. This keyword accepts two parameters. I: Date format (Required) and 2: separator character (optional). Default date format is *ISO and the default separator character is (-).

E.g. DATFMT (*JUL)

The possible values of date formats are as below:

§ *MDY=(MM/DD/YY)

§ *DMY=(DD/MM/YY)

§ *YMD=(YY/MM/DD)

§ *JUL=(YY/DD)

§ *USA=(MM/DD/YYYY)

§ *EUR=(DD.MM.YYYY)

§ *JIS=(YYYY-MM-DD)

o DATEDIT (Date Edit): DATEEDIT specifies the separator character for the Date format used. This keyword accepts 2 parameters 1. Date format 2. Separator Character. (Default is /). We can specify various date separator character as ‘-‘ ‘&’. E. g. DATEDIT (*YMD-)

o CURSYM (Current Symbol): CURSYM specifies the format of time literals and time fields within the program. The default is *ISO format with default separator as (.). This keyword accepts 2 parameters: 1. Time format (required) and 2: Separator (optional). The possible values are as follows:

§ *ISO=(HH.MM.SS)

§ *HMS=(HH:MM:SS)

§ *USA=(HH:MM: AM or HH:MM: PM)

E.g.TIMFMT (*USA).

F Specification

File Specification is used for declaring files in the program. It also describes how the files will be used within a program. In ILE RPG, F-specs use a combination of fixed notation and keyword notation. The fixed notation portion extends from position 7 to 42. The F-specs of ILE RPG have been modified to accommodate expanded length. The file name is expanded from 8 characters to10 characters and record-length is expanded from 4 characters to 5 characters.

Functions defined in RPG III are defined in terms of keywords in ILE RPG. Some of the examples are as below:

o RENAME (Old Record Format: New Record Format)-The RENAME keywords allow you to change a record-format name used in an externally described file. Example is as follows:

FMBMLO2 IF E K DISK RENAME (IPM500BM:IPM50r)

Here record format IPM500BM is renamed to IPM50R.

o PREFIX (prefix_string: nbr_of_char_replaced): The PREFIX keyword is used to partially rename the fields in externally described files. Prefix string is the string we want to use as a prefix and nbr_of_char_replaced specifies the number of characters to be replaced.

FMBMLO2 IF E K DISK PREFIX($L:2)

Fields of file MBMLO2 now will be starting from $L.

o SFILE (name_of_subfile: field_RRN): The SFILE keyword identifies any subfiles used in a display file included in a program. This keyword has 2 parameters:

§ Subfile name

§ Field, which stores Relative Record Number.

FTEMP CF E WORKSTN SFILE(subfile:field_RRN)

o USROPN: The USPORN keyword specifies that file is User Controlled. When this keyword is used, file must be opened with OPEN operation.

FITBAL IF E K DISK USROPN

D Specification

It is the new specification introduced by ILE for data definition. D specs can be used to define:

o Standalone fields including arrays and tables

o Named Constant

o Data Structures and their subfields.

D specs replace E-specs of RPG III. Following table explains D-Specs Format.

Statement Position	Purpose	Valid Values
6	Definition Specification	D
7-21	Name of field, array, table, named constant, data structure or data structure subfield.	Any valid symbol name
22	Data Structure Identification Externally described data structures Non-externally described data structures	E Blanks
23	Type of Data Structure: Program Status data structure Data Area data Structure Non-program status data structure or non data area data structure.	S U Blank
24-25	Type of Definition: Data structure Subfield Name constant Data Structure Standalone field or array Prototype Procedure Interface	Blank C DS S PP PI
26-32	From Position/keyword: Keywords for file information and program status data structure.	Blank I through 9999999 PROC, *STATUS
33-39	To position/length Data structure definition Field define LIKE another field Absolute end position Increase or decrease field size when defining a field LIKE another field	Blank 1 through 9999999 +/-1 through 99999
40	Internal type of field, subfield or array element Data, Time, Timestamp Signed & Unsigned Integer, Floating point Packed, Zone, Character	D,T,Z I,U,F P,S,A
41-42	Decimal Positions	0 through30
44-80	Keywords	E.g. ALT,DIM,INZ,LIKE
81-100	Comments	Optional

Examples:

1.Constant

D CMPNM C CONST (‘Midrange Computing’)

D LWR C ‘abcdefghjklmnopqrs-

Tuvwxyz’

D Twenty C CONST (20)

2.Standalone Field

D $flag S 2A INZ (*Blanks)

D &Name S LIKE (PRNAME)

D Specs permit us to consolidate data definition in a single place in your program.

The D spec EXTPGM keyword: The EXTPGM keyword indicates the external name of the program whose prototype is being defined. The name can be a character constant or a character variable. If EXTPGM is not specified, then the compiler assumes that you are defining a prototype for a procedure, and assigns it the external name found in positions 7-21.

Any parameters defined by a prototype with EXTPGM must be passed by reference; in addition you cannot define a return value. If the keyword EXTPGM is specified on the prototype, the call will be a dynamic external call; otherwise it will be a bound procedure call.

DcmdLinAP1 Pr EXTPGM(‘QUSCMDLM’)

C CAIIP CmdLinAPI

C Eval Inlr=On

In the given example, when you perform a call to the CmdLinAPI prototype, the API (built-in system program) QUSCMDLN will actually be called. API QUSCMDLN presents an OS/400 system command line for use within a program.

· I Specification

In RPG III, I specs are mainly used for field and record information and also defining data structures, data areas and named constant. In ILE RPG, all the data definition is consolidates in D specs at one area of program. Still I specs are used for defining program described files. In ILE RPG, there are many changes to the field entry I Specs:

o Expanded File name (up to 10 chars)

o Expanded Record length (up to 32766)

o External date/time format specifier(for program described file field)

o Date/time separator character.

· C Specification

ILE RPG C Specs provides free-form expression capabilities to some RPG operations. For example with the use of new EVAL operation we can perform free-form arithmetic expressions. We can also perform logical expression such as Conditional Branching and In ILE RPG, FACTOR1, FACTOR2 and RESULT fields have all been increased to 14 WHENEQ, UPDATE, DELETE, UNLOCK, RETURN, READPE, CHECKRE etc)

Blank lines are allowed and treated as a comment line.

EVAL Operation:

Eval Qname = Patext1 + Patext2

The expression for evaluation can contain the arithmetic operators +(addition), -(subtraction), *(multiplication), /(division) and **(exponentiation) as well as parenthesis, relational symbols(e.g.<,>), logical operators (e.g, AND, OR) and built-in functions.

Note:In the example given above, + sign indicates Concatenation.

If ($LEN>3)

Eval Cnt = $Cnt + 1

Endif

· P Specification

ILE RPG introduces concept of subprocedures. P-specs are used to define such Subprocedures and they denote the beginning and the end of the subprocedure. If we are passing any parameters to procedures, such parameter definition (i.e. procedure interface definition) takes place in D Specs.

When you describe P-specs, you describe prototyped procedures or sub-procedures. P-spec is the simplest ILE RPG specification. The P-specs were introduced when ILE RPG was enhanced to support sub-procedures.

RPG IV Description	Specification Position
6	Form Type (P)
7-21	Sub-procedure Name
24	Begin/End Procedure Code
44-80	Keywords

When a sub-procedure is defined, the main source section of the module containing the sub-procedure definition must contain a procedure prototype. Sub-procedure contain the following:

o A begin-procedure specification (b in position 24 of a procedure specification)

o A procedure-interface definition (if the procedure returns value or any parameters). The procedure interface must match the corresponding prototype.

o Other definition specifications of variables, constants and prototypes needed by the sub-procedure. These definitions are local definitions.

o Any calculation specification needed to perform the task of the procedure If the sub-procedure returns a value, then a return operation must be coded within the sub-procedure.

o An end-procedure specification (c in position 24 of a procedure specification).

The Procedure-interface definition may be placed anywhere within the definition specifications. But a sub-procedure must be coded in the order stated above.

Procedure name is required in begin-procedure specification. But the procedure name is optional in the end-procedure specification.

The P-Spec EXPORT Keyword

EXPORT is the only keyword for the P-spec. Export is used to indicate that this procedure can be invoked from another module in the program. With the EXPORT keyword specified, the sub-procedure can be bound to and can be called by any program.

If a module is entirely self-contained, EXPORT keyword is not required. Normally a sub-procedure is to encourage the reuse of code. Defining the sub-procedures outside of mainline code and using the EXPORT keyword enables this use.

· O Specification

The major differences between RPG III O specs and ILE RPG O specs are changes to:

o Accommodates 10 character file and field names.

o The continuation of literals (both ‘+’ or ‘-‘) and edit words

o Supports for larger space before and after values ( values from 0 to255are supported for space before and space after, skip before and skip after) and

o Supports for additional data formats (Z,D,T).

▪ Date and Time Data Types

Three data types deal with date and time related information: date, time and timestamp. Date and Time are self-explanatory. A timestamp is a combination of a date and time. RPG supports these data types in calendar-related operations, using certain operation codes and built in functions.

To define standalone fields with the date/time data types, you specify a D(for dates) T (for times) or Z (for time-stamps) in column 40. Each data type has a default length and display format (*ISO).]

The default display format for type date (D) is a 10-byte-long field with format yyyy-mm-dd. Time (T) has a default length of 8 bytes, with format hh. mm. ss. The default display format for timestamp (Z) has a length of 26 bytes, with format yyy-mm-dd-hh.mm.ss.mmmmmm.

The date and time data types allow alternative display formats (with the keyword DATFMT) to the defaults. Date supports eight different formats and Time supports five.

Following tables list the valid Date and Time formats:

DATFMT	Description	Representation	Example
*ISO	International Standards Org	yyyy-mm-dd	9999-12-31
*USA	IBM USA standard	mm/dd/yyy	12/31/9999
*EUR	IBM European standard	dd.mm.yyy	31.12.9999
*JIS	Japanese Industrial Standard	yyy-mm-dd	9999-12-31
*YMD	Year/month/day	Yy/mm/dd	99/12/31
*MDY	Month/day/year	mm/dd/yy	12/31/99
*DMY	Day/month/year	Dd/mm/yy	31/12/99
*JUL	Julian	Yy/ddd	99/365
TIMFMT	Description	Representation	Example
*ISO	International Standard Org	hh.mm.ss	23.59.59
*USA	IBM USA standard	hh.mm.xM	11.59 PM
*EUR	IBM European standard	hh.mm.ss	23.59.59
*JIS	Japanese Industrial Standard	hh.mm.ss	23.59.59
*HMS	Hours/minutes/seconds	hh.mm.ss	23.59.59

You can change default display format of date and time fields for a program as a whole by specifying the DATFMT and/or TIMFMT within the Control Specification. The separator is optional. If you specify an ampersand (&) as the separator, a blank is used as the separator character.

Related OPCODES:

ADDDUR
SUBDUR
EXTRACT

▪ New and enhanced Opcodes

The frequency used Opcodes, which are supported only in RPGLE, are as follows:

EVAL (Evaluate expression)

The EVAL operation code evaluates an assignment statement of the form result expression. The expression is evaluated and the result placed in result. Therefore, result cannot be a literal or constant but must be a field name, array name, array element, data structure data structure subfield, or a string using the %SUBST built-in function.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> LE12

FMT D DName+++++++++++ETDsFrom+++To/L+++IDc.Keywords+++++++++++++++++++++++++

*************** Beginning of data *************************************

0001.00 Dstr1 s 20a

0001.01 Dstr2 s 20a

0003.00 C eval str1='Dukestar Technologies'

0004.00 c EVALR str2='Dukestar Technologies'

0006.00 C str1 DSPLY

0006.01 C str2 DSPLY

0007.00 C eval *INLR = *on

****************** End of data ****************************************

F3=Exit F4=Prompt F5=Refresh F9=Retrieve F10=Cursor F11=Toggle

F16=Repeat find F17=Repeat change F24=More keys

Output of above function EVAL and EVALR is:

Display Program Messages

Job 090555/PB01U01SAL/QPADEV0009 started on 04/07/05 at 10:19:10 in subsystem Q

DSPLY Dukestar Technologie

DSPLY ukestar Technologies

Press Enter to continue.

F3=Exit F12=Cancel

Output of EVAL is Dukestar Technologie where s is ignored and EVALR is ukestar Technologies where D is ignored.

EXTRCT (Extract Date/Time/Timestamp)

The EXTRCT operation code will return one of:

o The year, month or day part of a date or timestamp field.

o The hours, minutes or seconds part of a time or timestamp field

o The microseconds part of the timestamp field.

The Date Time or Timestamp from which the information is required is specified in factor 2, followed by the duration code. The entry specified in factor2 can be a field, Factor 1 must be blank.

The result field can be any numeric or character field, subfield, array/table element. The result field is cleared before the extracted data is assigned. For a character result field, the data is put left adjusted into the result field.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> BIF51

FMT D DName+++++++++++ETDsFrom+++To/L+++IDc.Keywords+++++++++++++++++++++++++

*************** Beginning of data *************************************

0001.00 DLDT S D

0003.00 *

0004.00 C *USA MOVE *DATE LDT

0005.00 *extract month from above date

0006.00 C EXTRCT LDT:*M LMNTH 2 0

0006.01 c LMNTH dsply

0006.02 *extract date from above date

0007.00 C EXTRCT LDT:*D LDY 2 0

0007.01 c LDY dsply

0007.02 *extract year from above date

0007.03 C EXTRCT LDT:*Y LYR 4 0

0007.05 c LYR dsply

0008.00 C EVAL *INLR = '1'

****************** End of data ****************************************

F3=Exit F4=Prompt F5=Refresh F9=Retrieve F10=Cursor F11=Toggle

F16=Repeat find F17=Repeat change F24=More keys

· ADDDUR (ADD Duration)

The ADDDUR operation adds the duration specified in factor 2 to a date or time and places the resulting Date. Time or Timestamp in the result field.

Factor 1 is optional and may contain a Date, Time or Timestamp field, subfield, array ,array element, literal or constant. If factor1 contains a field name, array or array element then its data type must be the same data type as the field specified in the result field. If factor 1 is not specified the duration is added to the field specified in the result field.

Factor 2 is required and contains two subfactors. The first is duration and may be a numeric field, array element or constant with zero decimal positions. If the duration is negative then it is subtracted from the date. The second sub factor must be a valid duration code indicating the type of duration. The duration code must be consistent with the result field data type. You can add a year, month or day duration but not a minute duration to a data field.

The result field must be a date, time or timestamp data type field, array or array element if the result field is s time field, the result will always be a valid Time. For example adding 59 minutes to 23:59:59 would give 24:58:59. Since this time is not valid, the compiler adjusts it to 00:58:59. If factor 1 is blank, the duration is added to the value in the result field.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> BIF9

FMT H HKeywords++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

*************** Beginning of data *************************************

0001.00 DLDT S D

0003.00 *

0004.00 C *USA MOVE *DATE LDT

0005.00 *

0005.01 c ldt dsply

0005.02 c adddur 3:*m ldt

0006.01 c ldt dsply

0006.02 c adddur 3:*d ldt

0006.03 c ldt dsply

0006.04 c adddur 3:*y ldt

0006.05 c ldt dsply

0008.00 C EVAL *INLR = '1'

****************** End of data ****************************************

F3=Exit F4=Prompt F5=Refresh F9=Retrieve F10=Cursor F11=Toggle

F16=Repeat find F17=Repeat change F24=More keys

The output of above program is,

Display Program Messages

Job 090555/PB01U01SAL/QPADEV0009 started on 04/07/05 at 10:19:10 in subsystem Q

DSPLY 07.04.2005

DSPLY 07.07.2005

DSPLY 10.07.2005

DSPLY 10.07.2008

Press Enter to continue.

F3=Exit F12=Cancel

· SUBDUR (Subtract Duration)

The SUBDUR operation has been provided to:

o Subtract a duration to establish a new Date, Time or Timestamp

o Calculate a duration.

The SUBDUR operation can also be used to calculate duration between:

o Two dates

o A date and a timestamp

o Two times

o A time and a timestamp

o Two timestamps

Factor 1 is required and must contain a Date, Time or Timestamp field, subfield, array, array element, constant or literal.

Factor 2 is required and must also contain a Date, Time or Timestamp field, array ,array element, literal or constant. The duration code must be consistent with one of the following:

o Factor 1 and factor 2

o Years (*Y), Months (*M) and Days (D) if factor 1 and/or factor2 is a Date

o Timestamp, *Hours (*H),*Minutes(*MN) and *Seconds(*S) when factor1 and/or factor 2 is a Time or Timestamp.

The result of the calculation is a complete units; any rounding, which is done, is downwards. The calculation of duration includes microseconds.

For example, if the actual duration is 384 days, and the result is requested in years, the result will be 1 complete year because there are 1.05 years in 384 days. A duration of 59 minutes requested in hours will result in 0 hours.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> BIF9

FMT H HKeywords++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

*************** Beginning of data *************************************

0001.00 DLDT S D

0003.00 *

0004.00 C *USA MOVE *DATE LDT

0005.00 *

0005.01 c ldt dsply

0005.02 c subdur 3:*m ldt

0006.01 c ldt dsply

0006.02 c subdur 3:*d ldt

0006.03 c ldt dsply

0006.04 c subdur 3:*y ldt

0006.05 c ldt dsply

0008.00 C EVAL *INLR = '1'

****************** End of data ****************************************

F3=Exit F4=Prompt F5=Refresh F9=Retrieve F10=Cursor F11=Toggle

F16=Repeat find F17=Repeat change F24=More keys

The output of above program is,

Display Program Messages

Job 090555/PB01U01SAL/QPADEV0009 started on 04/07/05 at 10:19:10 in subsystem Q

DSPLY 07.04.2005

DSPLY 07.01.2005

DSPLY 04.01.2005

DSPLY 04.01.2002

Press Enter to continue.

F3=Exit F12=Cancel

List of Frequently used extended Opcodes

Sr.no.	RPGIII	RPGIV
1	REDPE	READPE
2	LOKUP	LOOKUP
3	UPDAT	UPDATE
4	DELET	DELETE
5	UNLCK	UNLOCK
6	SELEC	SELECT
7	WHXX	WHENXX
8	CASXX	CASEXX
9	DEFN	DEFINE
10	RETRN	RETURN
11	CHEKR	CHECKR
12	EXCPT	EXCEPT
13	SETOF	SETOFF
14	OCCUR	OCCUR

Built- In Functions:

RPG IV supports many built-in functions to return file-operation results, simplify complex calculations, perform string operations, and perform data-type conversions. BIF always begin with a % sign. They are coded within free-form expressions. To pass value to a built in function, enclose the values within parentheses immediately following the name of the BIF, separate multiple values with colon (;) separators.

%ABS (Absolute Value of Expression)

%ABS (numeric expression)

%ABS returns the absolute value of the numeric expression specified as the parameter. If the value of the numeric expression is non- negative, the value is returned unchanged. If the value is negative, the value returned is the value of the expression but with the negative sign removed.

%ABS may be used either in expressions or as parameters to keywords. When used with keywords, the operand must be a numeric literal, a constant name representing a numeric value, or a built-in function with a numeric value known at compile –time.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I1

*************** Beginning of data *************************************

0001.00 Df8 S 8f inz(-1)

0002.00 Di10 S 10i 0 inz(-123)

0003.00 Dp7 S 7p 3 inz(-1234.567)

0004.00 C eval f8=%abs(f8)

0004.01 * The value of "f8" is now 1.000000000000+E000

0005.00 C eval i10=%abs(i10-321)

0005.01 * The value of "i10" is now 444.

0006.00 C eval p7=%abs(p7)

0006.01 * The value of "p7" is now 1234.567.

0007.00 C eval *inlr=*on

****************** End of data ****************************************

%DEC (Convert to Packed Decimal Format)

% Dec (numeric expression {:precision: decimal places})

%DEC converts the value of the numeric expression to decimal (packed) format with precision digits and decimal p[laces decimal positions.

% DecH

%DECH (numeric expression: precision: decimal places)

%DECH is same as the %Dec built-in function, except half-adjust is applied to the value of numeric expression when converting to the desired precision. No message is issued if half adjust cannot be performed.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I2

*************** Beginning of data *************************************

0001.00 Dp7 S 7p 3 inz(1234.567)

0002.00 Ds9 S 9s 5 inz(73.73442)

0003.00 Df8 S 8f inz(123.456789)

0003.01 Dres1 S 15p 5

0003.02 Dres2 S 15p 5

0003.03 Dres3 S 15p 5

0004.00 C eval res1=%dec(p7)+0.011

0004.01 * The value of "res1" is now 1234.57800

0005.00 C eval res2=%dec(s9:5:0)

0005.01 * The value of "res2" is now 73.00000

0006.00 C eval res3=%dech(f8:5:2)

0006.01 * The value of "res3" is now 73.00000

0007.00 C eval *inlr=*on

****************** End of data ****************************************

%DECPOS (Get Number of decimal Positions)

%DecPost(numeric expression)

%DECPOS returns the number of decimal positions in the numeric expression.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I3

*************** Beginning of data *************************************

0001.00 DP7 S 7P 3 INZ(8236.567)

0002.00 DS9 S 9P 5 INZ(23.73442)

0003.00 DRES1 S 5I 0

0004.00 DRES2 S 5I 0

0005.00 DRES3 S 5I 0

0006.00 C EVAL RES1=%DECPOS(P7)

0006.01 * The value of "RES1" is now 3.

0007.00 C EVAL RES2=%DECPOS(S9)

0007.01 * The value of "RES2" is now 5.

0008.00 C EVAL RES3=%DECPOS(P7*S9)

0008.01 * The value of "RES2" is now 8.

0009.00 C EVAL *INLR=*ON

****************** End of data ****************************************

%EDITC (Edit Value Using an Editcode)

%EDITC (numeric: edit code)

%EDITC Returns a character result representing the numeric value edited according to the edit code.

%EDITC Example:

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I4

*************** Beginning of data *************************************

0001.00 Dmsg S 100A

0002.00 Dsalary S 9P 2 inz(1000)

0002.01 *

0002.02 * If the value of salary is 1000, then the value of salary * 12

0002.03 * is 12000.00. The edited version of salary * 12 using the A edit

0002.04 * code with floating currency is '$12,000.00'.

0002.05 * The value of msg is 'The annual salary is $12,000.00'

0002.06 *

0003.00 C eval msg='The annual salary is'

0004.00 C +%trim(%editc(salary * 12

0005.00 C :'A':*CURSYM))

0005.01 *

0005.02 * In the next example, the value of msg is 'The anuual salary is

0005.03 * &12,000.00'

0005.04 *

0006.00 C eval msg='The annual salary is'

0007.00 C +%trim(%editc(salary * 12

0008.00 C :'A':'&'))

0008.01 *

0008.02 * In the next example, the value of msg is 'Salary is

0008.03 * $*****12,000.00'

0008.04 *

0009.00 C eval msg='Salary is $'

0010.00 C +%trim(%editc(salary * 12

0011.00 C :'B': *ASTFILL))

0011.01 *

0011.02 * In the next example, the value of msg is 'The date is

0011.03 * 1/14/1999'

0012.00 C eval msg='The date is'

0013.00 C +%trim(%editc(*date:'Y'))

0014.00 C eval *inlr=*on

****************** End of data *************************************

%EDITW (Edit Value Using an Edit Word)

%EDITW (numeric: editword)

%EDITW Returns a character result representing the numeric value edited according to the edit word.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I5

*************** Beginning of data *************************************

0001.00 Damount S 50A

0002.00 Dsalary S 9P 2 inz(2451.53)

0003.00 Deditwd C '$ , , *Dollars& &Cents'

0003.01 *

0003.02 * If the value of salary is 2451.53, then the edited version of

0003.03 * (Salary * 12) is '$***29,418*Dollars 36 Cents'. The value of

0003.04 * amount is 'The annual salary is $***29,418*Dollars 36 Cents'

0003.05 *

0004.00 C eval amount='The annual salary is'

0005.00 C +%editw(salary * 12:editwd)

0005.01 C amount dsply

0006.00 C eval *inlr=*on

0007.00 * (In the constant 'edited', ('b' stands for blank spaces))

****************** End of data ****************************************

%ELEM( Get Number of Elements)

%ELEM(table_name)

%ELEM(array_name)

%ELEM returns the number of elements in the specified array or table.

%ELEM Example:

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I6

*************** Beginning of data *************************************

0001.00 Darrld S 20 DIM(10)

0002.00 Dtable S 10 DIM(20)ctdata

0003.00 Dnum S 5P 0

0003.01 *

0003.02 * like_array will be defined with a dimension of 10.

0003.03 * array_dims will be defined with a value of 10.

0003.04 *

0004.00 Dlike_array S like(arrld)dim(%elem(arrld))

0005.00 Darray_dims C const(%elem(arrld))

0005.01 *

0005.02 * In the following examples num will be equal to 10, 20, and 30.

0005.03 *

0006.00 C eval num=%elem(arrld)

0007.00 C eval num=%elem(table)

0008.00 C eval *inlr=*on

****************** End of data ****************************************

%FLOAT (Convert to Floating Format)

%FLOAT (numeric expression)

%FLOAT converts the value of the numeric expression to float format. This built- in function may only be used in expressions.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I7

*************** Beginning of data *************************************

0001.00 Dp1 s 15p 0 inz(1)

0002.00 Dp2 s 25p13 inz(3)

0003.00 Dres1 s 15p 5

0004.00 Dres2 s 15p 5

0005.00 Dres3 s 15p 5

0006.00 C eval res1=p1/p2

0006.01 * The value of 'res1' will be 0.33300

0007.00 C eval res2=%float(p1)/p2

0007.01 * The value of 'res2' will be 0.33333

0008.00 C eval res3=%float(p1/p2)

0008.01 * The value of 'res3' will be 0.33333

0009.00 C eval *inlr=*on

****************** End of data ****************************************

%INT (convert to integer)

%INT (numeric expression)

%INT converts the value of the numeric expression to integer. Any decimal digits are truncated. This built – in function may only be used in expressions. %INT can be used to truncate the decimal positions from a float or decimal value allowing it to be used as an array index.

%INTH

%INTH (numeric expression)

%INTH IS same as %Int, except half-adjust is applied to the value of the numeric expression when converting to integer type.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I8

*************** Beginning of data *************************************

0001.00 Dp6 s 5p 0

0002.00 Dp7 s 7p 3 inz(1234.567)

0003.00 Ds9 s 9s 5 inz(73.73442)

0004.00 Df8 s 8f inz(123.789)

0005.00 Dres1 s 15p 5

0006.00 Dres2 s 15p 5

0007.00 Dres3 s 15p 5

0008.00 Darray s 1a dim(200)

0009.00 Da s 1a

0010.00 C eval p6=%int(p7)

0011.00 * The value of "p6" is now 1234.

0012.00 C eval res1=%int(p7)+0.011

0012.01 * The value of "res1" is now 1234.01100

0014.00 c eval res2=%int(s9)

0014.01 * The value of "res2" is now 73.00000.

0016.00 C eval res3=%int(f8)

0016.01 * The value of "res3" is now 124.00000.

0018.00 C eval a=array(%inth(f8))

0018.01 * %INT and %INTH can be used as array indexes.

0019.00 C eval *inlr=*on

****************** End of data ****************************************

%LEN (Get Length)

%LEN(expression)

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I9

*************** Beginning of data *************************************

0001.00 Dnum1 s 7p 2

0002.00 Dnum2 s 5s 1

0003.00 Dnum3 s 5i 0 inz(2)

0004.00 Dchr1 s 10a inz('Toronto ')

0005.00 Dchr2 s 10a inz('Munich ')

0006.00 Dptr s *

0006.01 * Numeric expressions :

0007.00 C eval num1=%len(num1)

0009.00 C eval num1=%decpos(num2)

0011.00 C eval num1=%len(num1*num2)

0013.00 C eval num1=%decpos(num1*num2)

0013.01 * Character expressions :

0015.00 C eval num1=%len(chr1)

0017.00 C eval num1=%len(chr1+chr2)

0019.00 C eval num1=%len(%trim(chr1))

0021.00 C eval num1=%len(%subst(chr1:1:num3)

0022.00 C +''+%trim(chr2))

0024.00 C eval *inlr=*on

0025.00 * %len and %decpos can be useful with other built-in functions :

0026.00 * defloating point data types

%LEN Can be used to get the length of a variable expression or to set the current length of a variable-length field.

%SCAN (Scan for Characters)

% SCAN (search argument : source string {:start})

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I10

*************** Beginning of data *************************************

0001.00 Dsource s 15a inz('Dr. Doolittle')

0002.00 Dpos s 5u 0

0003.00 C eval pos=%scan('oo':source)

0004.00 C pos dsply

0004.01 * After the EVAL, pos = 6 because 'oo' begins at position 6 in

0004.02 * 'Dr. Doolittle'

0005.00 C eval pos=%scan('D':source:2)

0006.00 C pos dsply

0006.01 * After the EVAL, pos = 5 because the first 'D' found starting from

0006.02 * position 2 is in position 5.

0007.00 C eval pos=%scan('abc':source)

0008.00 C pos dsply

0008.01 * After the EVAL, pos = 0 because 'abc' is not found in

0008.02 * 'Dr. Doolittle'

0009.00 C eval pos=%scan('Dr':source:2)

0010.00 C pos dsply

0010.01 * After the EVAL, pos = 0 because 'Dr' is not found in

0010.02 * 'Dr. Doolittle', if the search starts at position 2.

0011.00 C eval *inlr=*on

****************** End of data *******************************

%Scan returns the first position of the search argument in the source string, or 0 if it was not found. If the start position is specified, the search begins at the starting position.

%SIZE (Get Size in Bytes)

%SIZE (variable)

%SIZE (literal)

%SIZE (array)

%SIZE (table)

% SIZE Returns the number of bytes occupied by the constant or field. The agreement may be a literal, a named constant, a data structure subfield, a field an array or a table name. It cannot, however, contain an expression.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I11

*************** Beginning of data *************************************

0001.00 Darr1 s 10 dim(4)

0002.00 Dtable1 s 5 dim(20)

0003.00 Dfield1 s 10

0004.00 Dfield2 s 9b 0

0005.00 Dfield3 s 5p 2

0006.00 Dnum s 5p 0

0007.00 Dcity s 40a inz('North York')

0007.01 *

0007.02 * calculation

0008.00 C eval num=%size(field1)

0010.00 C eval num=%size('HH')

0012.00 C eval num=%size(123.4)

0014.00 C eval num=%size(-03.00)

0016.00 C eval num=%size(ARR1)

0018.00 C eval num=%size(ARR1:*ALL)

0020.00 C eval num=%size(TABLE1)

0022.00 C eval num=%size(TABLE1:*ALL)

0024.00 C eval num=%size(field2)

0026.00 C eval num=%size(field3)

0028.00 C eval num=%size(CITY)

0030.00 c eval *inlr=*on

****************** End of data ****************************************

%SUBST (get Substring)

%SUBST(string start{:length})

%SUBST returns a portion of argument string. The start parameter represents the starting position of the sub string. The length parameter represents the length of substring. If it is not specified, the length of the string parameter less starts value plus one.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I12

*************** Beginning of data *************************************

0001.00 DMSG S 50A

0001.01 *

0002.00 C EVAL MSG = 'THE VALUE OF %SUBST IS : '

0003.00 C + %SUBST('HELLO WORLD':5+2)

0004.00 C MSG DSPLY

0004.01 *

0004.02 C EVAL MSG = 'THE VALUE OF %SUBST IS : '

0004.03 C + %SUBST('HELLO WORLD':5+2:10-7)

0004.04 C MSG DSPLY

0004.05 *

0004.06 C EVAL MSG = 'THE VALUE OF %SUBST IS : '

0004.07 C + %SUBST('ABCD'+'EFGH':5:3)

0004.08 C MSG DSPLY

0004.09 *

0005.00 C EVAL *INLR=*ON

****************** End of data ****************************************

%TRIM (trim Blanks at Edges)

%TRIM (string)

%TRIM Returns a string without leading and trailing spaces.

%TRIML (trim Leading Blanks)

%TRIML (string)

%TRIML returns a string without leading spaces.

%TRIMR (Trim Trailing Blanks)

% TRIMR (string)

%TRIMR returns a string without trailing spaces.

Columns . . . : 6 76 Edit PB01U01S/MYRPGLE

SEU==> I13

*************** Beginning of data *************************************

0001.00 DLOCATION S 16A

0001.01 DNAME S 20A

0002.00 *

0003.00 * LOCATION WILL HAVE THE VALUE 'TORONTO' ONTARIO'.

0004.00 *

0005.00 C EVAL LOCATION = %TRIM(' TORONTO, ONTARIO ')

0006.00 *

0007.00 * NAME WILL HAVE THE VALUE 'CHRIS SMITH'.

0008.00 *

0009.00 C MOVE(P) 'CHRIS' FIRSTNAME 10

0010.00 C MOVE(P) 'SMITH' LASTNAME 10

0011.00 C EVAL NAME =%TRIM(FIRSTNAME)+' '+%TRIM(LASTNAME

0011.01 *

0011.02 * LOCATION WILL HAVE THE VALUE 'TORONTO' ONTARIO'.

0011.03 *

0011.04 C EVAL LOCATION = %TRIML(' TORONTO, ONTARIO

0011.05 *

0011.06 * LOCATION WILL HAVE THE VALUE 'TORONTO' ONTARIO'.

0011.07 *

0011.08 C EVAL LOCATION = %TRIMR(' TORONTO, ONTARIO ')

0013.00 C EVAL *INLR=*ON

****************** End of data ****************************************

Converting RPG III programs to RPG IV programs

The process is carried out through the use of RPG/400 source member of a specified source physical file to the ILE RPG/400 format. CVTRPGSRC converts each source member on a line-by- line basis. The conversion tool presumes that the RPG source code is free of any compile error. Before you run the CVTRPGSRC command, there are few things you should understand and that you need to do:

· The CVTRPGSRC command operates on the source physical file member.

· Create a source file to receive the ILE RPG source members. The name IBM uses for ILE RPG source members is QRPGLESRC. The record length of the QRPGLESRC source file should be 112 bytes long. The basic format of an RPG IV statement is:

o 1-12: sequence number and date.

o 13-92: the executable portion of the RPG IV source code.

o 93-112: the comments section of RPG IV source.

· Make sure the source files containing your RPG/400 source members contain only RPG member types and no non-RPG “un-typed” source member. As CVTRPGSRC attempts to convert source member with a blank member type, you could end up wasting time.

o FROMFILE: Specifies the name of the source file that contains the RPG III or RPG/400 source code to be converted and the library where the source file is stored. This is a required parameter; there is no default file name.

o FROMMBR: Specifies the name(s) of the member to be converted. This is a required parameter; there is no default name.

o TOFILE: Specifies the name of the source file that contains converted source member and the library where the converted source file is stored. The converted source file must exist and should have a should have a record length of 112 characters.

o TOMBR: Specifies the name(s) of the converted source member(s) in the converted source file. If the value specified on the FROMMBR. Parameter is *ALL or generic*, then TOMBR must be equal to *FROMMBR.

o CVTRPT: Specifies whether or not a conversation report is printed.

§ *Yes: The conversion report is printed.

§ *No: The conversion report is not printed.

Summary

The CVTRPGSRC tool is by no means the most exciting part of ILE RPG, but it is probably the first step that many will take when they enter the new world of ILE.

AS/400 Forum

Sunday, December 15, 2013

Day-28.

Introduction To RPG IV:

Overview:

a. Understanding Of Basic Concepts RPG IV

b. Built In Function

Specification Name

H

F

D

I

C

P

O

RPG IV Description

Specification Position

Description

Representation

Example

TIMFMT

Description

Representation

Example

No comments:

Post a Comment