;+
; NAME:
;  addpath
; PURPOSE: (one line)
;  add a path to !path if it isn't already there
; DESCRIPTION:
;  
; CATEGORY:
;  Util
; CALLING SEQUENCE:
;  addpath, path
; INPUTS:
;  path - the path to add
; OPTIONAL INPUT PARAMETERS:
;  none
; KEYWORD INPUT PARAMETERS:
;  none
; KEYWORD OUTPUT PARAMETERS:
;  none
; OUTPUTS:
;  none
; COMMON BLOCKS:
;  None
; SIDE EFFECTS:
; RESTRICTIONS:
;  None
; PROCEDURE:
; MODIFICATION HISTORY:
;  2010 Feb 18 LAY
;  2011 Dec 21 LAY change to avoid call to PREF_SET
;-

pro addpath, path
    if strpos(!path,EXPAND_PATH(path)) eq -1 then begin
       pathsep = PATH_SEP(/SEARCH_PATH)
       !PATH = EXPAND_PATH('+'+path) + pathsep + !PATH   
       path_cache,/rebuild
    endif
;       PREF_SET, 'IDL_PATH', cpath(path)+':'+!path, /COMMIT  orig
end