Re: passing numeric data

[Scott Klement <klemscot@xxxxxxxxxxxx>]

The reason that I used pointers is because I'm paranoid about writing data
to an area of memory outside the scope of my variable.

In the data structure example you give here, if I were to pass a PACKED
parameter it'd be only 4 bytes long.   If I were to do this:

       c                   MOVE  *ZEROS            PARM1

3 zeroes would be put into whatever happened to be in the area of memory
that comes after my parameter.   This can cause all sorts of nasty and 
hard to debug errors.

Whereas, the way I was doing it, this can't happen.   Worst case scenario,
you'd try to use a field thats still based on a *NULL pointer, which the 
system would know is invalid and it could stop your program with an error.

Granted, if your careful, it won't matter.  :)   I have to wonder why you
say "why bother with pointers?".  IMHO, pointers arent any more of a
bother than data structures are.   



On Wed, 8 Mar 2000, Sims, Ken wrote:

> Hi Scott -
> 
> Why bother with pointers?
> 
>      d parm1           ds             7                    
>      d  zoned1                 1      7s 0                 
>      d  packed1                1      4p 0                 
>      d*                                                    
>      d myparm1         s              7  0                 
>      c*                                                    
>      c     *entry        plist                             
>      c                   parm                    parm1     
>      c*                                                    
>      c                   if        %subst(parm1:1:1) >= '0'
>      c                   eval      myparm1 = zoned1        
>      c                   else                              
>      c                   eval      myparm1 = packed1       
>      c                   endif                             
> 
> Ken
> Southern Wine and Spirits of Nevada, Inc.
> Opinions expressed are my own and do not necessarily represent the views of
> my employer or anyone in their right mind.
> 
> 

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