Function:     FTSD_INSERT

Purpose:      Inserts record of DESCRIPTOR in HEADER.

Category:     FITS

File:         ftsd_access.c

Author:       Sjag Steensma (K.G. Begeman)

Use:          INTEGER FTSD_INSERT( HEADER,      Input	  CHARACTER*(*)
                                   DESCRIPTOR,  Input     CHARACTER*(*)
                                   RECORD )	input	  CHARACTER*(*)

              FTSD_INSERT   Returns:
                             >=0 : Offset of record used in header
			    -4	 : No room in header.
              HEADER        Contains FITS header to put record in
              DESCRIPTOR    FITS search descriptor
              RECORD	    Record to put in record of DESCRIPTOR in
              		    HEADER.
Description:
	FTSD_INSERT looks for a record with descriptor DESCRIPTOR. If found,
	RECORD is copied to the record found. If not found, a record with
	a blank descriptor is searched. If found, RECORD is copied there
	else -4 is returned.
	The descriptors COMMENT and HISTORY are always added to the header
	(i.e. a blank descriptor is searched) since these descriptors may
	occur more than once in a header.

Updates:
	Aug 14, 1990: Sjag; document created.