DSCDIR.DOC 
 
	DSCDIR - FORTRAN PROGRAM TO PRODUCE A DIRECTORY OF DSC TAPES.
 
 
      MODIFICATIONS:
 
      28-Aug-81, WB-004 do not unload tape after rewind
      11-Jun-81, wb-003 fix error with empty and short directories
      10-Jun-81, WB-002 fix problems with error on .DIR files
      10-Jun-81 WB-001 Allow 1600 bpi tape
		William D. Burton, Jr.
		Texas Research Institute of Mental Sciences
		1300 Moursund
		Houston, Texas  77030
		(713) 797-1976  ext 501
 
	This file describes the program DSCDIR, a FORTRAN-IV-PLUS program
which produces a directory of tapes written by DSC (Disk-Save-and-Compress)
Utility.  It has worked on both RSX and IAS systems.
 
INSTALLATION:
 
	1. Distribution of DSCDIR consists of:
 
		DSCDIR.FTN - Main program and subroutines
		DSCDIR.CMD - Task build command file
		DSCDIR.DOC - This file
 
	2. Compile the main program DSCDIR.FTN
	3. Edit the task-build command file for your installation
	   e.g. resident libraries etc.
 
OPERATION:
 
	1. The DSC tape to be scanned is UNMOUNTED on fortran LUN-3
		DSCDIR uses direct QIO reads (subroutine RDTAPE).
		The program does NOT require reading all reels of
		a multi-reel tape set.
 
	2. Run DSCDIR and answer the questions.  DSCDIR will not accept
		indirect command file input.
 
		a. prompt = INPUT TAPE SPECIFIER [DDU:]
		   answer - name of the tape device holding DSC tape.
			    (e.g. MT1:)
 
		b. prompt = TAPE DENSITY (800 OR 1600 BPI)? [I]
		   answer - density of input tape, integer 800 or 1600
		  	    default is 800 bpi.
 
		c. prompt = PRINT CONTENTS OF DIRECTORY FILES [Y/N]
		   answer - Y if a listing of the contents of the Files-11
			    disk directories is wanted.
			    N to suppress this list.
 

DSCDIR.DOC (continued)
 
		d. DSCDIR will read the tape and print a summary of:
		   1) ANSI standard file labels (80 characters)
		   2) FILES-11 file headers
				file-id
				file-name, extension, version
				creation date and time
		   3) DSC initialization information (first reel of DSC
			tape set only)
 
 
LIMITATIONS:
 
	1. The predecessor of this program was used in checking out the
	   file-restoring program DSCCPY.  This program should be fairly
	   robust.
 
	2. If DATA OVERRUN errors occur (error code -13. IE.DAO), the
	   program buffer size can be increased by changing
	   PARAMETER NRLTH=    to the desired size.  NRLTH should never
	   be less than 1040. bytes.
 
	3. If multiple tapes are directoried out of sequence, FALSE error
	   messages FILE NUMBER OF DATA BLOCK DID NOT MATCH will be printed
	   these messages can be ignored.