FXBCLOSE
Name
	FXBCLOSE
Purpose
	Close a FITS binary table extension opened for read.
Explanation
	Closes a FITS binary table extension that had been opened for read by
	FXBOPEN.
Use
	FXBCLOSE, UNIT
Inputs
	UNIT	= Logical unit number of the file.
  
 Opt. Inputs : 
	None.
Outputs
	None.
  
 Opt. Outputs: 
	None.
Keywords
	ERRMSG	  = If defined and passed, then any error messages will be
		    returned to the user in this parameter rather than
		    depending on the MESSAGE routine in IDL.  If no errors are
		    encountered, then a null string is returned.  In order to
		    use this feature, ERRMSG must be defined first, e.g.
			ERRMSG = ''
			FXBCLOSE, ERRMSG=ERRMSG, ...
			IF ERRMSG NE '' THEN ...
Calls
	None.
  
 Common      : 
	Uses common block FXBINTABLE--see "fxbintable.pro" for more
	information.
Restrictions
	The file must have been opened with FXBOPEN.
Side Effects
	None.
Category
	Data Handling, I/O, FITS, Generic.
  
 Prev. Hist. : 
	W. Thompson, Feb. 1992.
  
 Written     : 
	William Thompson, GSFC, February 1992.
  
 Modified    : 
	Version 1, William Thompson, GSFC, 12 April 1993.
		Incorporated into CDS library.
	Version 2, William Thompson, GSFC, 21 June 1994
		Added ERRMSG keyword.
      
       Version 3, William Thompson, GSFC, 23 June 1994
              
               Modified so that ERRMSG is not touched if not defined.
Version
     
       Version 3, 23 June 1994
	Converted to IDL V5.0   W. Landsman   September 1997