Index for Section 9

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get_def_partitionmap(9r)
NAME
  get_def_partitionmap - Disk: Calculates a default partition map

SYNOPSIS
  int get_def_partitionmap(
	  register struct DEVGEOMST *geom,
	  register struct pt_tbl *pmap );

ARGUMENTS
  geom
      Specifies a pointer to the disk's geometry structure.

  pmap
      Specifies a pointer to the partition map to be filled in.

DESCRIPTION
  The get_def_partitionmap interface calculates a default partition map when
  supplied with a disk geometry. It uses the disk capacity and sector size
  for the calculation and ignores other aspects of the geometry.  The
  partitions are layed out as follows:

    ·  Partition a

       Starts at block 0 and spans the number of blocks specified by the
       global variable ddr_def_partsz_a.

    ·  Partition b

       Starts after partition a and spans the number of blocks specified by
       the global variable ddr_def_partsz_b.

    ·  Partition c

       Spans the entire disk.

    ·  Partitions d, e, and f

       Are undefined with lengths of zero.

    ·  Partition g

       Starts after partition b and spans half of the remainder of the disk.

    ·  Partition h

       Starts after partition g and spans the remainder of the disk.

  The get_def_partitionmap interface is called by a disk device driver's open
  interface and DIOCGDEFPT ioctl command to create a default partition map.







EXAMPLE
  See Writing Device Drivers: Advanced Topics for a code example of the
  get_def_partitionmap interface.

RETURN VALUES
  Upon successful completion, get_def_partitionmap returns the value zero
  (0). Otherwise, it returns the value 1 to indicate the partition map could
  not be updated.

SEE ALSO
  ioctl Commands: DEVGETGEOM(9r)

  Data Structures: DEVGEOMST(9s), pt_tbl(9s)

Index for Section 9

Alphabetical listing for G

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