Function:     FTSI_GETR

Purpose:      Gets float data from a FITS tape.

Category:     FITS

File:	      fts_io.c

Author:       P. Roelfsema

Use:	      INTEGER FTSI_GETR( MTID,		Input	       INTEGER
				 ARRAY, 	Output	       REAL
				 ARRLEN,	Input	       INTEGER
				 TID	  )	Input/Output   INTEGER

	      FTSI_GETR Returns:
			  >0 - number of reals transferred to ARRAY.
		   -1 .. -10 - tape error (see MTIODEV.DC2)
			 -11 - not a FITS file.
			 -12 - found and skipped tape label
			 -13 - double tape mark found, tape skipped back to
			       before second tape mark.
			 -20 - could not get enough memory for internal ftsbuf.
			 -22 - conversion error.
			 -30 - tried to read from a tape (MTID) which is
			       unknown to the FTS* routines.
			       (occurs e.g. when FTSI_GETR is called
			       before FTSD_GETH)
			 -31 - cannot read backwards ( ARRLEN < 0 )
	      MTID	A device unit number as obtained from MTOPEN.
	      ARRAY	Target array for the data.
	      ARRLEN	Length of ARRAY
	      TID	Tranfer ID from FTSD_GETH.
			If > zero on output more data is left on
			tape, thus subsequent calls of FTSI_GETR are
			nessecary. TID=0 ends a series of calls.
			TID=0 occurs at the end of file mark. After
			TID=0 the tape is positioned before the end of file.

Updates:
	Jun 27, 1990, PRR, Document created.
	Sep 12, 1990: SS,  Adjustments for new data structure.
	Sep 17, 1990: SS,  Added parameter nskip.