Example: Perform Date Arithmetic

Example: Perform date arithmetic

This program illustrates how to write a CL program that adds or subtracts a given number of days for the current system date.

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/* Calculate new date from current system date. Pass negative */

/* number to subtract, positive number to add */

/* */

/* The first parameter is a character 8 date in YYYYMMDD format */

/* or the special value *CURRENT */

/* */

/* The second parameter is a decimal value for the number of days */

/* to adjust the first parameter by */

/* */

/* Test cases: CALL CALCDATE (*CURRENT -5) */

/* CALL CALCDATE (*CURRENT 5) */

/* CALL CALCDATE ('20030225' -90) */

/* CALL CALCDATE ('30020228' 90) */

/* */

/* There is no error handling in this sample, so make sure the */

/* input dates are valid (that is, no 20031325). The valid date */

/* date range is Oct 14 1582 to Dec 31 9999 */

/* */

PGM PARM(&curdate &DAYSTOCHG)

DCL VAR(&CURDATE) TYPE(*CHAR) LEN(8)

DCL VAR(&DAYSTOCHG) TYPE(*DEC) LEN(15 5)

DCL VAR(&DATETIME) TYPE(*CHAR) LEN(17)

DCL VAR(&DATE) TYPE(*CHAR) LEN(8)

DCL VAR(&LILDATEINT) TYPE(*CHAR) LEN(4)

DCL VAR(&LILDATEDEC) TYPE(*DEC) LEN(10 0)

DCL VAR(&ERRCOD) TYPE(*CHAR) LEN(4) +

VALUE(X'00000000')

DCL VAR(&MSG) TYPE(*CHAR) LEN(50)

IF COND(&CURDATE = '*CURRENT') THEN(DO)

CALL PGM(QWCCVTDT) PARM('*CURRENT' ' ' '*YYMD' +

&DATETIME &ERRCOD) /* Get current system +

date and time in YYYYMMDD */

CHGVAR VAR(&DATE) VALUE(%SST(&DATETIME 1 8)) /* Get +

just the date portion */

ENDDO

ELSE CMD(CHGVAR VAR(&DATE) VALUE(&CURDATE)) /* +

Use the date provided */

CALLPRC PRC(CEEDAYS) PARM(&DATE 'YYYYMMDD' +

&LILDATEINT *OMIT) /* Get Lilian date for +

current date */

CHGVAR VAR(&LILDATEDEC) VALUE(%BIN(&LILDATEINT)) /* +

Get Lilian date in decimal format */

CHGVAR VAR(&LILDATEDEC) VALUE(&LILDATEDEC + +

&DAYSTOCHG) /* Adjust specified number +

of days */

CHGVAR VAR(%BIN(&LILDATEINT)) VALUE(&LILDATEDEC) /* +

Get Lilian date in integer format */

CALLPRC PRC(CEEDATE) PARM(&LILDATEINT 'YYYYMMDD' +

&DATE *OMIT) /* Return calculated date in +

YYYYMMDD format */

CHGVAR VAR(&MSG) VALUE('The new date is ' *CAT &DATE)

SNDPGMMSG MSG(&MSG) TOPGMQ(*EXT)

ENDPGM

Parent topic:Examples: CL programs and procedures