One of the cool things about CL (even though I rarely, if ever, use it anymore) is that it is extendable. But one thing it does badly is date manipulation. Effectively, it only handles decimal fields that contain something similar to a date. It is up to the programmer to come up with creative techniques to manipulate date values.
One of the things RPG IV does exceptionally well is date arithmetic. So why not leverage that capability by creating a new CL command that adds a duration to a date value from within CL?
The first thing you have to do is decide in what format the input and output date values will be specified. Since CL uses the job date format extensively, that is the format I've selected for this example command.
The Add Date Duration (ADDDUR) command adds the indicated number of dates to the base date and returns the resulting date to the CL variable specified on the RTNDATE parameter.
You declare a six-digit character variable in CL and populate it with the starting date for the command, calling ADDDUR with the duration you want to add to that date. The duration is added and the resulting date is returned in *JOBRUN format, which is the same as the job date format.
The following is the source for the ADDDUR CL command.
/* ------------------------------------------- */
/* Command processing program is: ADDDUR */
/* ------------------------------------------- */
/* COMPILE WITH: ALLOW(*IPGM *BPGM) */
/* ------------------------------------------- */
/* ----------------------------------------------- */
/* DATE(*TODAY | *SYSDATE) are the equivalent. */
/* DATE(*JOBDATE | *JOBRUN) are the equivalent. */
/* DATE(*SBMJOB) is the date the job was */
/* submitted. (aka, submitted-on date). */
/* All other values are based on the system */
/* date not the job-start date. */
/* ----------------------------------------------- */
PARM KWD(DATE) TYPE(*DATE) DFT(*JOBDATE) +
SPCVAL((*TODAY 000000) (*SYSDATE 000000) +
(*TOMORROW 000001) (*YESTERDAY 000002) +
(*JOBDATE 000003) (*JOBRUN 000003) +
(*SBMDATE 000004)) PROMPT('Base Date')
PARM KWD(DURATION) TYPE(*INT4) DFT(1) +
PROMPT('Number of days to add')
/* Returned date is always in Job Date Format */
PARM KWD(RTNDATE) TYPE(*CHAR) LEN(6) RTNVAL(*YES) +
CHOICE('Rtn Format: Job Date Format') +
PROMPT('CL var. Return Date')
ADDDUR Parameters
DATE is the input date value. This value must be specified in job date format if specified in a CL variable. If a date literal is specified, it may be in MMDDYYYY, MMDDYY, or CYYMMDD format. It accepts dates returned in job date format from the RTVJOBA command.
In addition to a date value, the following special values may be specified:
- *TODAY--Today's date, based on the system date (not the job date)
- *SYSDATE--Same as *TODAY, but can be used to be more clear about the date
- *JOBDATE or *JOBRUN--The job date
- *SBMDATE--The date the job was submitted to the job queue
- *YESTERDAY--The date prior to the current system date
- *TOMORROW--The date following the current system date
DURATION is the number of days you want to add to the date specified on the DATE parameter. The duration may be any number--negative, zero, or positive.
RTNDATE specifies a six-position character CL variable that will receive the returned date value in job date format.
To add seven days to today's system date, do the following:
To retrieve tomorrow's date, do this:
The following RPG IV program, ADDDUR, is the command processing program for the ADDDUR command. It performs the date arithmetic. Specify this program when compiling the ADDDUR command.
H DFTACTGRP(*NO)
** © 2005 by Robert Cozzi, Jr.
** All rights reserved.
D ADDDUR PR
D inDate 7A Const
D nDur 5I 0 Const
D rtnDate 6A
D ADDDUR PI
D inDate 7A Const
D nDur 5I 0 Const
D rtnDate 6A
D Today S D Inz(*SYS)
D JOBDate S D Inz(*JOB)
D Job S 26A
D IntrnlJobID S 16A
D SBMDate S 8A
/INCLUDE QSYSINC/QRPGLESRC,QUSRJOBI
/INCLUDE QSYSINC/QRPGLESRC,QUSEC
D PSDS SDS
D JobName 10A Overlay(PSDS:244)
D JobUser 10A Overlay(PSDS:254)
D JobNbr 6A Overlay(PSDS:264)
D CvtDate PR ExtPgm('QWCCVTDT')
D inFmt 10A Const OPTIONS(*VARSIZE)
D inDate 64A Const OPTIONS(*VARSIZE)
D outFmt 10A Const OPTIONS(*VARSIZE)
D outDate 64A OPTIONS(*VARSIZE)
D api_error Like(QUSEC) OPTIONS(*VARSIZE)
D RtvJobA PR ExtPgm('QUSRJOBI')
D rtnBuffer 32767A OPTIONS(*VARSIZE)
D nRtnBufLen 10I 0 Const
D FmtName 8A Const
D Job 26A Const
D IntrnlJobID 16A Const
D api_error Like(QUSEC) OPTIONS(*VARSIZE)
D newDate S D
D baseDate S D
C eval *INLR = *ON
C SELECT
** Today?
C When inDate = '0000000'
C MOVE Today BaseDate
** Tomorrow?
C When inDate = '0010000'
C Today AddDur 1:*DAYS BaseDate
** Yesterday?
C When inDate = '0020000'
C Today SubDur 1:*DAYS BaseDate
** Job date?
C When inDate = '0030000'
C MOVE JOBDATE BaseDate
** Submitted-on Date? *SBMDATE
C When inDate = '0040000'
C eval Job = JobName + JobUser + JobNbr
C clear QUSEC
C clear QUSI030000
C eval QUSBPRV = %size(QUSEC)
C Callp RtvJobA(QUSI030000:%size(QUSI030000) :
C 'JOBI0300' : JOB : IntrnlJobID :
C QUSEC)
C if QUSBAVL > 0 or QUSDPOJ = *BLANKS
C Move JobDate BaseDate
C else
C eval SbmDate = QUSDPOJ
C callp CvtDate('*DTS':QUSDPOJ:'*YYMD':
C SbmDate : QUSEC )
C *ISO0 MOVE SbmDate BaseDate
C endif
** User-specified date
C OTHER
C *CYMD0 TEST(DE) inDate
C if %Error
C move today baseDate
C return
C endif
C *CYMD0 move InDate baseDate
C endSL
C TEST(E) baseDate
C if %Error
C eval rtnDate = ' '
C return
C endif
C baseDate AddDur nDur:*DAYS newDate
C *JOBRUN0 MOVE newDate rtnDate
C return
Example of Using ADDDUR
DCL VAR(&TOMORROW) TYPE(*CHAR) LEN(6)
RTVJOBA DATE(&MYDATE)
ADDDUR DATE(&MYDATE) DURATION(1) RTNDATE(&TOMORROW)
In this example, the job's date is retrieved into a six-position character variable named &MYDATE. The RTVJOBA command is used to retrieve the date. RTVJOBA always returns the job date as a character value in the job date format.
Then, the ADDDUR command is called to add one day to the job date. The &MYDATE variable contains the job date from the prior RTVJOBA command. The DURATION parameter indicates that one day is added to the value in &MYDATE, and the new date is returned into the &TOMORROW variable, again in job date format.
ADDDUR helps with one of the most difficult issues with respect to CL: date arithmetic. The results can be used in OPNQRYF, embedded SQL (if available), and user interfaces (display files).
The source code for this article and many other RPG tools is available for free download at the RPGIV.com Web site. Click on the free RPG IV downloads link.
Bob Cozzi is a programmer/consultant, writer/author, and software developer. His popular RPG xTools add-on subprocedure library for RPG IV is fast becoming a standard with RPG developers. His book The Modern RPG Language has been the most widely used RPG programming book for more than a decade. He, along with others, speaks at and produces the highly popular RPG World conference for RPG programmers.
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