Re: Help defining a command...

I ran a RTVCMDSRC against DSPJOBLOG.  You can see how they condition for 
outfile from there.  hth
/*           CRTCMD     CMD(*LIBL/DSPJOBLOG) +   */
/*                      PGM(QSYS/QMHDSPJL) +   */
/*                      SRCFILE(ROB/QCMDSRC) +   */
/*                      SRCMBR(DSPJOBLOG) +   */
/*                      THDSAFE(*NO) +   */
/*                      MLTTHDACN(*SYSVAL) +   */
/*                      TEXT('Display Job Log') +   */
/*                      VLDCKR(*NONE) +   */
/*                      MODE( +   */
/*                        *ALL) +   */
/*                      ALLOW( +   */
/*                        *ALL) +   */
/*                      ALWLMTUSR(*YES) +   */
/*                      MAXPOS(2) +   */
/*                      PMTFILE(QDEVELOP/QCPFPMT) +   */
/*                      MSGF(*LIBL/QCPFMSG) +   */
/*                      HLPSHELF(*LIST) +   */
/*                      HLPPNLGRP(*LIBL/QHMHCMD) +   */
/*                      HLPID(DSPJOBLOG) +   */
/*                      HLPSCHIDX(*NONE) +   */
/*                      CURLIB(*NOCHG) +   */
/*                      PRDLIB(*NOCHG) +   */
/*                      PMTOVRPGM(*NONE) +   */
/*                      AUT(*USE) +   */
/*                      REPLACE(*YES) +   */
/*                      ENBGUI(*YES)   */

/*  Internal info   */
/*    PGM call state:           *SYSTEM   */
/*    CCSID:                    37   */

             CMD        PROMPT('Display Job Log')
             PARM       KWD(JOB) +
                        TYPE(Q0176) +
                        DFT(*) +
                        SNGVAL( +
                          (* )) +
                        PROMPT('Job name')
             PARM       KWD(OUTPUT) +
                        TYPE(*CHAR) +
                        LEN(1) +
                        RSTD(*YES) +
                        DFT(*) +
                        SPCVAL( +
                          (* ) +
                          (*PRINT L) +
                          (*APIDFN M) +
                          (*OUTFILE N)) +
                        EXPR(*YES) +
                        PROMPT('Output')
             PARM       KWD(OUTFILE) +
                        TYPE(Q0263) +
                        FILE(*OUT) +
                        CHOICE(*NONE) +
                        PMTCTL(P0350) +
                        PROMPT('File to receive output')
             PARM       KWD(OUTMBR) +
                        TYPE(E01F0) +
                        CHOICE(*NONE) +
                        PMTCTL(P0350) +
                        PROMPT('Output member options')
Q0176:       QUAL       TYPE(*NAME) +
                        LEN(10) +
                        MIN(1) +
                        EXPR(*YES)
             QUAL       TYPE(*NAME) +
                        LEN(10) +
                        EXPR(*YES) +
                        PROMPT('User')
             QUAL       TYPE(*CHAR) +
                        LEN(6) +
                        RANGE( +
                          '000000' +
                          '999999') +
                        FULL(*YES) +
                        EXPR(*YES) +
                        PROMPT('Number')
E01F0:       ELEM       TYPE(*NAME) +
                        LEN(10) +
                        DFT(*FIRST) +
                        SPCVAL( +
                          (*FIRST )) +
                        EXPR(*YES) +
                        PROMPT('Member to receive output')
             ELEM       TYPE(*CHAR) +
                        LEN(7) +
                        RSTD(*YES) +
                        DFT(*REPLACE) +
                        SPCVAL( +
                          (*REPLACE REPLACE) +
                          (*ADD ADD)) +
                        EXPR(*YES) +
                        PROMPT('Replace or add records')
Q0263:       QUAL       TYPE(*NAME) +
                        LEN(10) +
                        MIN(1) +
                        EXPR(*YES)
             QUAL       TYPE(*NAME) +
                        LEN(10) +
                        DFT(*LIBL) +
                        SPCVAL( +
                          (*LIBL ) +
                          (*CURLIB '*CURLIB   ')) +
                        EXPR(*YES) +
                        PROMPT('Library')
P0350:       PMTCTL     CTL(OUTPUT) +
                        COND( +
                          (*EQ 'N'))
             DEP        CTL(&JOB *NE *) +
                        PARM( +
                          (&OUTPUT *NE 'N')) +
                        MSGID(CPD240F)
             DEP        CTL(&JOB *NE *) +
                        PARM( +
                          (&OUTPUT *NE 'M')) +
                        MSGID(CPD2524)
             DEP        CTL(&OUTPUT *EQ 'N') +
                        PARM( +
                          (&OUTFILE *NE ' ')) +
                        MSGID(CPD9861)
             DEP        CTL(&OUTMBR *NE *FIRST) +
                        PARM( +
                          (&OUTFILE *EQ ' ')) +
                        NBRTRUE(*EQ 0) +
                        MSGID(CPD9867)
             DEP        CTL(&OUTPUT *NE 'N') +
                        PARM( +
                          (&OUTFILE *EQ ' ')) +
                        MSGID(CPD9862) 

Rob Berendt