sys

  sys [[d:]path] d: [bootsect] [switches]

Options

  [[d:]path]
  The (optional) location of the system files.
  If not given, the current directory is assumed.

  d:
  The drive to make bootable.

  bootsect
  The name of file, to which the 512-byte boot sector image
  will be written.
  (the drive's real boot sector won't be
   written to unless BOTH is used.)

Switches:

  /BOTH
  The new boot sector will be written to the image file
  and to the actual drive boot sector.

  /BOOTONLY
  With this option the boot sector (or image) will be updated,
  but the kernel and command.com will
  not be copied to the destination.

  /K filename
  Gives the filename of the kernel file to be copied. This option
  is only required when the kernel is not called "kernel.sys"

  /L segment
  The load segent, in hexadecimal, to use. The default is 0x60.

  /B btdrv
  Sets the BIOS boot drive # stored within the boot sector.

  /FORCEDRV
  Causes the boot sector to only use the btdrv indicated in
  boot sector.  NOPs the code that normally uses BIOS provided
  drive # passed at boot time in the DL register.

  /BACKUPBS [path]filename
  The original boot sector is written to [path]filename prior
  to overwriting with FreeDOS one.  The filename may refer to any
  [image or bs] file, if exists only the 1st 512 bytes will be
  overwritten.

  /RESTORBS [path]filename
  Restores original boot sector ([path]filename) and exits.
  The boot sector specified is written with no modifications.
  The filename may refer to any [image or bs] file, only the 1st
  512 bytes are used.