Re: FLUSH [was: Mixed language programming Tcl/Tk and Fortran (Windows)]

From: James Giles (jamesgiles_at_worldnet.att.net)
Date: 10/02/03 

Date: Thu, 02 Oct 2003 18:51:37 GMT

Jan C. Vorbrüggen wrote:
>>> As for doing this automatically (your question to Ron), I don't see how
>>> this can be done in a general way.
>>
>> Then you haven't read the thread.
>
> Why do you elect to be needlessly insulting whenever the slightest
> opportunity arises?

If you insist on taking offence, that's your choice. I was pointing out
that the correctness of flush after every WRITE has already been
established (and accepted) as being obviously correct (in the sense
of never omitting a flush that's needed). Flush after every WRITE
can obviously be automated. And it's completely general.

>> In his case, it's trivially obvious
>> that automatically flushing after all WRITEs is sufficient.
>
> Yes, after all WRITEs that belong to one transaction. How does your
> run-time system determine where one transaction ends, and the next one
> begins?

*EVERY* WRITE is a transaction. It is a transaction between the
program and the system (with the I/O library as an intermediary).
A flush after *every* WRITE is sufficient to guarantee correctness.
It isn't necessary, but it's sufficient. 

-- 
J. Giles

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