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From: sandmann AT clio DOT rice DOT edu (Charles Sandmann)
Message-Id: <10201271840.AA25808@clio.rice.edu>
Subject: _bios_disk doc?
To: eliz AT is DOT elta DOT co DOT il (Eli Zaretskii),
   djgpp-workers AT delorie DOT com (DJGPP developers)
Date: Sun, 27 Jan 2002 12:40:08 -0600 (CST)
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Reply-To: djgpp-workers AT delorie DOT com

Eli helpfully replied to a problem on our newsgroup:

> > If I run this code after booting to the dos prompt using a Win98 boot disk
> > it returns a status of 0x01 (Invalid request or a bad command).
>
> Here's why:
>
> >  di.sector   = 0;
>
> The first sector on a disk is number 1, not zero.

This is taken from the example code for _bios_disk.

Proposed patch - OK to commit? :

*** b_disk.bak	Sun Sep 27 09:21:02 1998
--- b_disk.txh	Sun Jan 27 12:38:50 2002
*************** struct diskinfo_t @{
*** 19,23 ****
    unsigned head;        /* Head number. */
    unsigned track;       /* Track number. */
!   unsigned sector;      /* Sector number. */
    unsigned nsectors;    /* Number of sectors to read/write/verify. */
    void    *buffer;      /* Buffer for reading/writing/verifying. */
--- 19,23 ----
    unsigned head;        /* Head number. */
    unsigned track;       /* Track number. */
!   unsigned sector;      /* Sector number. (1-63) */
    unsigned nsectors;    /* Number of sectors to read/write/verify. */
    void    *buffer;      /* Buffer for reading/writing/verifying. */
*************** di.drive    = 0x80;
*** 129,133 ****
  di.head     = 0;
  di.track    = 0;
! di.sector   = 0;
  di.nsectors = 1;
  di.buffer   = &record_buffer;
--- 129,133 ----
  di.head     = 0;
  di.track    = 0;
! di.sector   = 1;
  di.nsectors = 1;
  di.buffer   = &record_buffer;