17.9 Example

Here is a slightly longer example of a script declaration block.

  
# A machine from the good old days (?)
decl {
  ! The original IBM PC XT from 1983, complete with
  ! a <em>full-height</em> 10 MB fixed disk and a 5 1/4" floppy drive.

  # Note that comments (like this one) are distinct from doc strings.

  param ram_size : int = 256
  ! RAM size in KiB. Max is 640, which should be enough for anyone.

  param cpu_freq : float = 4.77
  ! CPU frequency in MHz.

  param video : {mda, cga, hercules} = cga
  ! Type of video card. mda &amp; hercules look best.

  group "networking"
  param mac_addr : string or nil = NIL
  ! Ethernet MAC address, or NIL if no Ethernet adapter present.

  param rom_file : file("*.bin") = "%script%/pc_xt_rom.bin"
  ! File containing the ROM image. Must be exactly 40 KiB.

  param rtc_time : string = "2015-02-01 13:37:00"
  ! Initial time and date of the real-time clock, on the form
  ! <tt>"YYYY-MM-DD HH:MM:SS"</tt>.

  # Include parameters declared in another file.
  params from "ms-dos.simics"

  # Override the default value of a parameter from that file
  default dos_ver = "2.11"

  result system : string
  ! Name of generated system component object.
}

# Here the actual script starts with commands to execute.