CLOSE procedure closes the
file units specified as arguments. All
open files are also closed when IDL exits.
, ..., Unit
The IDL file units to close.
Set this keyword to close all open file units. In addition, any file units that were allocated via GET_LUN are freed.
Set this keyword to close all file units from 1 to 99. File units greater than 99, which are associated with the
FREE_LUN procedures, are not affected.
If file units 1 and 3 are open, they can both be closed at the same time by entering the command:
CLOSE, 1, 3