;+
; Project
;           SolarB EIS
;
; Name
;           EIS_OPEN_DB
;
; Purpose
;           General purpose function used to open database table (based
;           on keyword)
;
; Category
;           EIS timeline planning
;
; Written
;           Chunkey Lepine, RAL, 12-Feb-2005
;
; HISTORY
;           v0.1 JAR 12-Sep-2006
;               Test that DB file can actually be opened
;-
;************************************************************************
FUNCTION eis_open_db , _EXTRA = ex

db_name = eis_get_db_name(_EXTRA = ex)
IF (db_name EQ '') THEN RETURN , -1

dbhname = find_with_def(db_name+'.dbh', 'ZDBASE')
;print,dbhname
; Check database files are readable
OPENR , lun , dbhname , ERROR = err , /GET_LUN
IF (err EQ 0) THEN BEGIN
    CLOSE    , lun
    FREE_LUN , lun
ENDIF ELSE BEGIN
    MESSAGE  , !ERROR_STATE.msg , /INFORMATIONAL
    RETURN   , err
END

index = WHERE(TAG_NAMES(ex) EQ 'UPDATE' , count)
IF (count EQ 1) THEN dbopen , db_name , 1 , unavail = unavail $
    ELSE dbopen, db_name, unavail = unavail

RETURN, 1

END