Check for IFS object (link)

With the use of the AS/400 (iSeries) Integrated File System (IFS) becoming more widely spread, wouldn't it be nice...

to be able to check for the existence of an object (link) before attempting to use it? Here's how I did it.

CL program CHKOBJLNKC:

 
/*  CHECK OBJECT LINK   */
             PGM        PARM(&OBJ &OBJERROR)

             DCL        VAR(&OBJ)        TYPE(*CHAR) LEN(512)
             DCL        VAR(&OBJERROR)   TYPE(*LGL)

             DCL        VAR(&OFF)        TYPE(*LGL)           VALUE('0')
             DCL        VAR(&ON)         TYPE(*LGL)           VALUE('1')
             DCL        VAR(&SPLF)       TYPE(*CHAR) LEN(10)  VALUE(CHKOBJLNK)

/*  TURN ERROR FLAG OFF   */
             CHGVAR     VAR(&OBJERROR) VALUE(&OFF)

/*  CHECK TO SEE IF THE OBJECT EXISTS   */
             OVRPRTF    FILE(*PRTF) HOLD(*YES) SPLFNAME(&SPLF) +
                          OVRSCOPE(*CALLLVL)

             DSPLNK     OBJ(&OBJ) OUTPUT(*PRINT) OBJTYPE(*ALL) +
                          DETAIL(*BASIC) DSPOPT(*USER)
             MONMSG     MSGID(CPFA0A9) EXEC(CHGVAR VAR(&OBJERROR) +
                          VALUE(&ON))

/*  DELETE THE SPOOL FILE   */
             DLTSPLF    FILE(&SPLF) SPLNBR(*LAST)
             MONMSG     MSGID(CPF0000)

             ENDPGM 

Command CHKOBJLNK:

 
/*  CHECK OBJECT LINK   */
             CMD        PROMPT('Check object link')

             PARM       KWD(OBJ) TYPE(*PNAME) LEN(512) MIN(1) +
                          PROMPT('Object Link to check')

             PARM       KWD(OBJERROR) TYPE(*LGL) RTNVAL(*YES) +
                          PROMPT('Object error')

Compile the CL program CHKOBJLNKC. Then compile the command CHKOBJLNK -- specifying PGM(CHKOBJLNKC) on the compile options. Now you have a simple command to call wherever you want to check for the existence of an IFS object.

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