stand alone modules (no service program) and handling file I/O

        Good Morning all, I have just started using more ILE type of
programming and really have liked what I have seen here on the list lately.
My question is this.

        I have 5 modules compiled into an ILE program. 4 of them are work
modules that do a little formatting and validation. The 5th module is the
driving program that will be doing a conversion. ( A One time only run ).
The 4 validation modules generally are modules that I will be able to use in
other conversion programs down the road.
        The 4 work modules each open a file or two in the course of the
processing. Currently I have each of these modules set up as Prototyped
Calls (Function calls?) the last parm passed into these modules is an action
parm. when this action code is OPEN all the work modules just open the
files. When CLOSE, they close the files. Anything else means do the work. I
am just not sure if this is how I HAVE to do this but I certainly dont want
to Open and Close these files every single time that they are used by the
driving program. An example of the simplest module is below. ANy comments ?
One thing to remember is that the programming manager does NOT want any
service programs created at this time. (   for now anyway  :)    )

        Thanks

        C                   Select

        C                   When      Action = @Open

        C                   OPEN      OPLDUZ8


*-----------------------------------------------------------------------

        C                   When      Action = *Blank

        C     Sloc          Chain     OPLDUZ8                            50

        C     '01':'YN'     XLATE     *IN50         FOUND

        C                   Dow       FOUND = YES

        C     Sloc          ReadE     OPLDUZ8
50
        C     '01':'YN'     XLATE     *IN50         FOUND

        C                   EndDo

        C                   Eval      retfield = DzSlin + 1


*-----------------------------------------------------------------------

        C                   When      Action = @Close

        C                   Close     OPLDUZ8

        C                   EndSL



        C                   RETURN    retField

        P CVMSLOCSEQ      E

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