The following code snippet should give you an idea of how you would have a job check itself for running every three weeks, i.e. weeks 1, 4, 7, 10, etc…

PGM

DCL VAR(&WEEKNO) TYPE(*DEC) LEN(1 0)
DCL VAR(&DTAARA) TYPE(*CHAR) LEN(10) VALUE(‘MYWEEKNO’)
DCL VAR(&DTAARALIB) TYPE(*CHAR) LEN(10) VALUE(‘QGPL’)
DCL VAR(&NOWEEKS) TYPE(*DEC) LEN(1 0) VALUE(3)

/* Retrieve the current “week number” from the data area. If the */
/* data area doesn’t exist then create it… */

RTVDTAARA DTAARA(&DTAARALIB/&DTAARA) RTNVAR(&WEEKNO)
MONMSG CPF1015 EXEC(DO)
CRTDTAARA DTAARA(&DTAARALIB/&DTAARA) TYPE(*DEC) LEN(1 +
0) VALUE(0)
CHGVAR VAR(&WEEKNO) VALUE(0)
ENDDO

/* Increase the “week number” by 1 and then compare it to the run */
/* frequency. If the Week Number is greater than the frequency then */
/* reset it to “1″ and update the data area… */

CHGVAR VAR(&WEEKNO) VALUE(&WEEKNO + 1)
IF COND(&WEEKNO *GT &NOWEEKS) THEN(CHGVAR +
VAR(&WEEKNO) VALUE(1))

CHGDTAARA DTAARA(&DTAARALIB/&DTAARA) VALUE(&WEEKNO)

/* If this is not the 1st week of the run cycle then exit the CL… */

IF COND(&WEEKNO *NE 1) THEN(RETURN)

/* …otherwise continue with the job… */

ENDPGM

The data area name and library and the run frequency are coded in variables to allow for easier maintenance and portability. With a little modification the program can be adapted to accept these variables as parameters and return a flag identifying whether the calling CL should continue or not.

All the best

Jonathan