NetNews Offline 2/NetNews Offline Volume 2.iso/news/comp/lang/c-part1/5424

Internet Message Format | 1996-08-05 | 1.8 KB

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From: Lawrence Kirby <[e-mail]>
Newsgroups: comp.lang.c
Subject: Re: Using C for real time data collection
Date: Fri, 09 Feb 96 13:29:09 GMT
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References: <4fdou7$[e-mail]>
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In article <4fdou7$[e-mail]>
           [e-mail] "kbatch" writes:

>I have a data collection program written mostly in C that uses stream
>functions. Problem: someone inadvertantly shut off the computer during
>data collection - all data was lost. The files are left open purposely
>for data review and efficiency. I want to link with commode.obj. Will
>the operating system (DOS) automatically commit the data to disk when
>the stream buffer becomes full?

Not necessarily. There are a lot of DOS specific issues here such as whether
you have write-caching on the drive and whether DOS updates file information
(such as recorded length) while the file is held open. You need to discuss
these more fully but in a DOS related newsgroup.

>Or, do I have to use a fflush after each
>fwrite?

If you want to be sure that the contents of the C stream buffers have been
written out to the OS, yes, unless you set the stream to be non-buffered with
setbuf or setvbuf. However fflush() does not force the OS to write the data
to disk. For more information about DOS specifically try
comp.os.msdos.programmer.

--
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Lawrence Kirby | [e-mail]
Wilts, England | [e-mail]
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