;+
;
; @file_comments
; For internal use of SAXO
;   1) define key_forgetold = 1b - keyword_set(flag)
;   2) remove all oldcm_used.pro found in !path
;   3) define and create myuniquetmpdir and add it to !path
;   4) copy oldcm_full(_empty) to myuniquetmpdir+'oldcm_used.pro'
;   5) make sure that the common variables are correctly initialized.
;   6) merge the online_help if possible...
;
; @categories
; Compatibility
;
; @param flag {in}{optional}
; 1 or 0 to keep or forget the compatibility
;
; @uses
; cm_general
;
; @examples
; keep_compatibility, 0
;
; @history
; Sebastien Masson (smasson\@lodyc.jussieu.fr)
;                      June 2005
;
; @version
; $Id$
;
;-
PRO keep_compatibility, flag
;
  compile_opt idl2, strictarrsubs
;
@cm_general
;
  IF n_elements(myuniquetmpdir) NE 0 THEN return
;
; version should be at least 6.0
;
  IF fix(strmid(!version.release, 0, 1)) LT 6 THEN BEGIN
    print, '                   *** ***** ***'
    print, '                   *** ERROR ***'
    print, '                   *** ***** ***'
    print, 'This version of SAXO needs at least IDL version 6.0'
    print, '                   *** ***** ***'
    print, '                   *** ERROR ***'
    print, '                   *** ***** ***'
    return
  ENDIF
; are we using the virtual machine??
  IF n_elements(key_vm) EQ 0 THEN key_vm = lmgr(/vm)
; are we using gdl or idl??
  defsysv, '!gdl', exist = key_gdl
;
  if n_elements(flag) eq 0 then flag = 1b - keyword_set(key_forgetold)
; 1) automatic definition of key_forgetold
  key_forgetold = 1b - keyword_set(flag)
;
; 2) remove all oldcm_used.pro found in !path
  to_rm = find('oldcm_used')
  IF to_rm[0] NE 'NOT FOUND' THEN file_delete, to_rm
;
; 3) define and create myuniquetmpdir and add it to !path
  def_myuniquetmpdir
; if we are using the virtual machine, there is no need to do this
  IF NOT keyword_set(key_vm) THEN BEGIN
;
; 4) copy oldcm_full(_empty) to myuniquetmpdir+'oldcm_used.pro'
; select which file should be copied to oldcm_used.pro
    IF key_forgetold THEN BEGIN
      oldcm = find('oldcm_empty')
      print, 'We forget the compatibility with the old version'
    ENDIF ELSE BEGIN
      oldcm = find('oldcm_full')
      print, 'We keep the compatibility with the old version'
    ENDELSE
;
    oldcm = oldcm[0]
    IF oldcm EQ 'NOT FOUND' THEN BEGIN
      print, 'Error: oldcm_full or oldcm_empty must be found in the !path'
      stop
    ENDIF
; copy
    file_copy, oldcm, myuniquetmpdir + 'oldcm_used.pro', /overwrite
;
; make sure we can make the plots even if we are using the demo mode
;
    demomode_compatibility
  ENDIF
;
; 5) make sure that the common variables are correctly initialized.
;
  IF size(ccmeshparameters, /type) NE 8 THEN BEGIN
    computegrid, 1, 1, 1, 1, 1, 1, /fullcgrid
@cm_4data
    varname = ''
    vargrid = 'T'
    vardate = '0'
    varexp = ''
    varunit = ''
    valmask = 1.e20
  ENDIF
;
; 6) merge the online_help if possible...
;
  mergeonline_help
;
  return
END