OpenEuphoria

RE: Checking file integrity

• Posted by mistertrik at hotmail.com Apr 22, 2003
• 385 views

excess line
excess line

How about reading both files in to your program, and doing a checksum on 
them? It would be slow, but if you read the file in as you went, then 
perhaps that could be faster.
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\__| Mr Trick





>From: rforno at tutopia.com
>Reply-To: EUforum at topica.com
>To: EUforum <EUforum at topica.com>
>Subject: RE: Checking file integrity
>Date: Mon, 21 Apr 2003 14:10:03 -0300
>
>a
>a
>a
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>Lines to cheat Topica last glitch...
>Rob:
>I just tried this approach (comparing reported file size and actual bytes
>read) as previously advised to me by Pete Lomax.
>However, although I know some file is corrupted because Nero refuses to 
>read
>it (it stops with "read error" while trying to copy the CD), my program 
>does
>not detect any difference between sizes, so I think some of the bytes read
>should be wrong.
>Wouldn't be it possible for Euphoria to return an error report in such a
>case, for example with a negative number different from -1 (EOF)?
>Maybe I'm wrong, but I think the OS has a variable called errno (under C)
>that can be accessed by the user. Couldn't it be used to that end?
>Regards.
>
>----- Original Message -----
>From: Robert Craig <rds at RapidEuphoria.com>
>To: EUforum <EUforum at topica.com>
>Sent: Monday, April 21, 2003 2:36 AM
>Subject: Re: Checking file integrity
>
>
> > > The attached program tries to verify file integrity.
> > > I ran this program on a data CDROM, which I know has errors because 
>Nero
> > > stops with "read error" when trying to copy it. However, the program
>does
> > > not detect
> > > any error. Am I doing something wrong?
> >
> >
> > I don't know what you expected to happen.
> > Your program seems to just read each file
> > until it encounters a -1 (end of file).
> > If a file has been corrupted, maybe you will
> > get a -1 prematurely. Euphoria itself will never
> > report an error. Maybe you should count the number of
> > bytes and compare with the size in the dir() entry.
> >
> > Regards,
> >     Rob Craig
> >     Rapid Deployment Software
> >     http://www.RapidEuphoria.com
> >
> >
> > TOPICA - Start your own email discussion group. FREE!
> >
> >
>
>
>TOPICA - Start your own email discussion group. FREE!
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