NAME

bblist − format of bad block list

SYNOPSIS

#include <dev/badblk.h>

DESCRIPTION

The bad block structure contains a list of damaged st506 sectors on the device, plus a replacement sector (within the bad block cylinder). 

The structure of the bad block list as given in the include file is:

/∗
 ∗Format of the bad sector replacement track,
 ∗and associated data structures.
 ∗
 ∗Maximum number of bad blocks we can handle.
 ∗This number must be such that the "badblk_hdr" fit onto 512 bytes.
 ∗/
 #defineBB_MAX84
 typedefunsigned  shorttrack_address;
 typedefstruct{
unsigned  shortcylinder;
track_addressblock;
}  disc_address;
 structbadblk_hdr{
unsigned  bb_magic;/∗  Magic number  ∗/
unsigned  bb_number; /∗  No of bad blocks  ∗/
disc_addressbb_blocks[BB_MAX];
track_addressbb_replacement[BB_MAX];
};
  #defineBB_MAGIC ((‘B’ << 24) | (‘a’ << 16) | (‘d’ << 8) | (‘!’ << 0))
#defineBB_OFFSET4

Two copies of the bad block list structure are kept on the device. The layout of the cylinder is defined in ptable(5). 

SEE ALSO

bbutil(8), ptable(5)

4.2 Berkeley Distribution  —  Revision 1.3 of 11/01/89