;+
;
; @file_comments
; set X or Z devices with the good arguments...
; defined key_batch to use IDL in batch mode through the Z buffer
;
; @categories
; devide managment and default definitions
;
; @examples
;
;   set_default_device
;
; @keyword BATCH {in}{optional}{type=0 or 1}
; define this keyword to 0 or 1 to force the definition of key_batch
; if neither this keyword or key_batch are defined, define set
; key_batch based on <proidl>FSTAT</proidl> result
;
; @history
;
;   * August 2012: creation by pinsardf and massons
;     thanks to fstat help and
;     http://idl.tamu.edu/headless_X.html for z-buffer usage
;     IDL instruction HELP,/FILES,-2,-1,0 might also be usefull here
;
; @version
;
; $Id$
;
; $URL$
;
;-
pro set_default_device, BATCH = batch
;
  compile_opt idl2, strictarrsubs
;
@cm_general
;
; define key_batch if it not already done...
  IF n_elements(batch) EQ 0 THEN BEGIN 
    IF n_elements(key_batch) EQ 0 THEN BEGIN   ; if not already defined
      fstat0_structure = FSTAT(0)              ; automatic definition
      key_batch = 1 - fstat0_structure.isatty
    ENDIF
  ENDIF ELSE key_batch = batch  ; force the definition with batch keyword
;
  IF keyword_set(key_batch) THEN BEGIN
    set_plot, 'Z'
; nb of colors is set to 8 in order to allow color number from 0 to 256
    device, SET_PIXEL_DEPTH = 8, Z_BUFFERING = 0
  ENDIF ELSE BEGIN 
    thisOS = strupcase(strmid(!version.os_family, 0, 3))
    CASE thisOS of
      'WIN': SET_PLOT, thisOS
      ELSE: SET_PLOT, 'X'
    ENDCASE
  ENDELSE
  device, DECOMPOSED = 0 ; use color indexes
; force background color index to the last color (white)
  !p.BACKGROUND = (!d.n_colors-1) < 255
; force drawing color index to the first color (black)
  !p.color = 0
  IF !d.name EQ 'Z' THEN erase  ; apply these changes in !p
;
  RETURN
END