compile subroutine exports_column_valid(ConvType, DataIo, Branch, ReturnedValue)
begin condition
pre:
post:
end condition

$insert logical
$insert exports_equ
$insert msg_equates
declare function msg, get_property, set_property
equ valid$         to 0    ;* successful
equ invalid_msg$   to 1    ;* bad data       -   print error message window
equ invalid_conv$  to 2    ;* bad conversion -          "         "
equ invalid_nomsg$ to 3    ;* bad but do not print the error message window

ReturnedValue = DataIo       
status() = Valid$  
*
begin case
   case ConvType = 'ICONV'
      if Branch = 'Columns' then
          VInfo = get_property( @window, '@Columns' )
          ErrMsg = 'Not a Valid Column '
      end else
          if Branch = 'BtreeColumns' then
              VInfo = get_property( @window, '@BtreeColumns' )
              ErrMsg = 'Not a valid Btree Column '
          end else
              VInfo = get_property( @window, '@QColumns' )
              ErrMsg = 'Not a valid Non Indexed Column'
          end
      end
      locate DataIo in VInfo using @vm setting Dum else
          MsgInfo = ''
          MsgInfo<micon$> = '!'
          MsgInfo<mtext$> = ErrMsg:'Press [SF2] for a valid listing...'
          Void = msg( '', MsgInfo )
          status() = invalid_nomsg$
      end
   case ConvType = 'OCONV'
      * no output
      ReturnedValue = DataIo
   case otherwise$
      ReturnedValue = ''
      status() = invalid_conv$
end case
return