RE: explicit close

[Buck Calabro <buck.calabro@xxxxxxxxxxxxxxxxx>]

Scott Mildenberger wrote:

>I know your response said typical 
>I/O functions but what is your
>opinion on functions such as 
>GetCustName or ValidStation 
>that aren't obviously doing any I/O?  

Instead of including a test for %open and an open in each and every I/O
routine, it always seemed cleaner (to me) to have an explicit fileOpen and
fileClose routine.

>The user of the function doesn't 
>really know if files are open/closed 
>(nor should they care).  

I agree that this is the ideal place to be, but to be honest, I'm not sure
of the best path to Nirvana.

>I tend to take the approach
>that the files used in a service 
>program are USROPN and they 
>are opened by the first procedure 
>that uses them.  

I started that way but now I like the idea of a public fileOpen, fileClose
and fileStatus function.  That way the caller can determine when to
open/close and if it is indeed open or not.  It's a case of where do you
prefer to do the if %open: in the caller or in the procedure.  I lean toward
the former even though it exposes more of the I/O module's guts to the
caller.  I have been doing work using commitment control, and the "caller
controlled" open/close/commit seems to be more natural in that environment.

>I usually just leave the file open
>unless it is a file/procedure that 
>isn't typically used very often.  I know
>this can leave a number of files 
>open in interactive jobs but I haven't
>noticed any problems with this, 
>although that doesn't mean there 
>aren't any.

I haven't seen problems either.  Synon programs do the same thing and there
can be A Lot of open files - typical jobs have over a hundred open files at
a time with no apparent problems.  Like I said earlier, in a commitment
control environment, you really want to be aware of "pending updates."  If
you need to track the end of a transaction, you may as well track the end of
the "session" as well.  Saves yourself from uncommitted records...

Buck Calabro
Aptis; Albany, NY
"We are what we repeatedly do.
 Excellence, then, is not an act, but a habit." --Aristotle


Billing Concepts Corp., a NASDAQ Listed Company, Symbol: BILL
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