; $Id: dm_define_pointer.pro,v 1.6 2005/02/07 20:03:58 qiuym Exp $
;#######################################################################
;
; NAME:
;  dm_define_pointer
;
; PURPOSE:
;  define a dave_pointer
;
; CATEGORY:
;  dcs_mslice
;
; AUTHOR:
;  Yiming Qiu
;  NIST Center for Neutron Research
;  100 Bureau Drive, Gaithersburg, MD 20899-8562
;  United States
;  yiming.qiu@nist.gov
;  Feb, 2005
;
; LICENSE:
;  The software in this file is written by an employee of
;  National Institute of Standards and Technology
;  as part of the DAVE software project.
;
;  The DAVE software package is not subject to copyright protection
;  and is in the public domain. It should be considered as an
;  experimental neutron scattering data reduction, visualization, and
;  analysis system. As such, the authors assume no responsibility
;  whatsoever for its use, and make no guarantees, expressed or
;  implied, about its quality, reliability, or any other
;  characteristic. The use of certain trade names or commercial
;  products does not imply any endorsement of a particular product,
;  nor does it imply that the named product is necessarily the best
;  product for the stated purpose. We would appreciate acknowledgment
;  if the DAVE software is used or if the code in this file is
;  included in another product.
;
;#######################################################################

function dm_define_pointer
    defsysv,'!dave_defaults',exists=exists
    re_def =   0
    if exists eq 0 then re_def=1 $
    else if ptr_valid(!dave_defaults) eq 0 then re_def=1
    if re_def eq 1 then begin
       cd,current = thisDir
       pdd=ptr_new({datDir:thisDir,workDir:thisDir,PDFReader:'',web_browser:''})
       defsysv,'!dave_defaults',pdd
    endif
    defsysv,'!DAVE_AUXILIARY_DIR',exists=exists ;should exist if starts from dave
    if not exists then begin
        file = file_which('dcs_DetPos2.dat',/INCLUDE_CURRENT_DIR)
        if  float(!version.release) ge 6.0 then $
            path = file_dirname(file,/mark_directory) $
        else begin
            if float(!version.release) ge 5.5 then pathsep = call_function("path_sep") $
            else pathsep = !delimiter   ;!delimiter is declared in dcs_mslice.pro
            id   = strpos(file,pathsep,/reverse_search)
            path = strmid(file,0,id+1)
        endelse
        defsysv,'!DAVE_AUXILIARY_DIR',path
    endif
    davesysvars
    dave_makedaveptr,davePtr=davePtr
    dcs_defineDaveStructure,davePtr=davePtr
    dcs_sysvars,davePtr=davePtr
    return,davePtr
end