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From:	Paul Wilkins <disk AT paradise DOT net DOT nz>
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Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Interpreting return value from _bios_disk
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Date:	Wed, 28 Jul 2004 22:15:32 +1200
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Goh, Yong Kwang wrote:
> Hi.
> 
> I'm writing a simple program to read read a floppy at the sector
> level, so I'm using _bios_disk.
> 
> Apparently, there are some bugs in the documentation and example for
> _bios_disk.
> After reading some previous postings by other users, it appears to me
> that
> 
> the line in the example:
> 
> di.buffer = &record_buffer;
> 
> ought to be changed to:
> 
> di.buffer = record_buffer;
> 
> since record_buffer is declared as: 
> 
> char record_buffer[512];

That makes good sense.

> Secondly, the way of interpreting the return value is not just
> comparing it to zero for success and non-zero otherwise. Since AL also
> contains the number of sectors read (I'm only currently experimenting
> with _DISK_READ so far),
<snip>

If it helps here's some example code of biosdisk()

Code to probe floppy geometry. For Turbo C, DJGPP, or Watcom C.
http://my.execpc.com/~geezer/osd/boot/size.c

-- 
Paul Wilkins

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