Trailing-Edge
-
PDP-10 Archives
-
decuslib20-03
-
decus/20-0081/dtape.doc
There is 1 other file named dtape.doc in the archive. Click here to see a list.
******************* DTAPE DOCUMENTATION **********************
MNEMONICS:
CMD COMMAND
DIS DISPOSITION (GENERATION-LEVEL OR 0)
GEN GENERATION-LEVEL OR GENERATION-COUNT
LDV LOGICAL-DEVICE
MRS MINIMUM-REEL-SIZE FOR MOUNTING SCRATCHES
NEW NEW VALUE FOR FIELD BEING CHANGED
RCD RETENTION-CODE (RULE FOR CALCULATING RETENTION DATES)
RDT RETENTION-DATE
RPG REELS-PER-GENERATION FOR MOUNTING SCRATCHES
SIZ SIZE OF REEL (0300FT, 0600FT, 1200FT, 2400FT)
USE USE OF TAPE (INPUT OR OUTPUT)
VID VISUAL-IDENTIFICATION (NAME OF GENERATION GROUP)
VOL VOLUME NUMBER
WHO WHO IS USER (JOB STEP OR PROGRAMMER NAME)
WHT WHAT (DETERMINES OPTION OF COMMAND)
CONCEPTS:
A. VOLUME NUMBER (VOL=)
EACH TAPE CARRIES A VOLUME NUMBER (PHYSICAL TAPE NUMBER)
WHICH UNIQUELY IDENTIFIES EACH REEL OF TAPE IN THE LIBRARY.
THIS NUMBER APPEARS ON BOTH THE REEL-FACE AND THE
TAPE-SEAL OR CANISTER.
THE VOLUME NUMBER IS A POSITIVE NUMBER OF UP TO 4 DIGITS.
VOLUME NUMBERS ARE ASSIGNED TO THE REELS BY THE USER WHEN
NEW TAPES ARE ADDED TO THE LIBRARY AND REMAIN WITH THE TAPES
REGARDLESS OF HOW THEY ARE USED.
OCCASIONALLY A BAD TAPE WILL BE DISCARDED OR REPLACED.
IF A TAPE IS DISCARDED,ITS VOLUME NUMBER MUST BE DELETED
FROM THE SYSTEM. IF A TAPE IS REPLACED, THE OLD TAPE IS DE-LABELED
AND DISCARDED, AND THE NEW TAPE IS GIVEN THE OLD VOLUME NUMBER.
TAPE STORAGE MUST BE ORGANIZED BY VOLUME NUMBER.
WHENEVER TAPES ARE MOUNTED, THEY ARE CALLED FOR BY VOLUME
NUMBER ONLY. MULTI-REEL FILES APPEAR AS A STRING OF VOLUME
NUMBERS SEPARATED BY HYPHENS IN THE VID PORTION OF THE MOUNT
MESSAGE.
B. VISUAL IDENTIFICATION (VID=)
IN ADDITION TO THE VOLUME-LABELS ON EACH TAPE, EVERY
NON-SCRATCH TAPE CARRIES A VID-LABEL SPECIFYING THE GENERATION-GROUP
OF WHICH IT IS A MEMBER. THIS LABEL MAY ALSO PROVIDE OTHER
INSTALLATION DEFINED DATA SUCH AS REEL-OF,CREATION DATE,
CREATION TIME, DEVICE, ETC.
THE VID IS A 6 CHARACTER ALPHANUMERIC FIELD.
DTAPE CATALOGS EVERY TAPE UNDER ITS APPROPRIATE VID. SCRATCH
TAPES ARE ASSIGNED TO ONE OF FOUR SPECIAL VID'S (0300FT,
0600FT, 1200FT, 2400FT) ACCORDING TO SIZE.
WITHIN A VID, TAPES ARE CATALOGED ACCORDING TO GENERATION-LEVEL;
AND WITHIN GENERATION-LEVEL, REEL-NUMBER OF THE FILE.
REEL-NUMBER IS NOT TO BE CONFUSED WITH VOLUME-NUMBER;
THE FIRST REEL OF A FILE IS REEL-NUMBER 1, ETC.
C. GENERATION LEVEL (GEN=)
EACH GENERATION OF A GIVEN VID IS ASSIGNED A NUMERIC GENERATION
LEVEL ACCORDING TO THE RELATIVE AGE OF THE GENERATION.
GENERATION LEVELS ARE EXPRESSED AS NEGATIVE VALUES HAVING
THE FOLLOWING MEANINGS:
GENERATION LEVEL MEANING
-1 MOST RECENTLY CREATED
-2 2ND MOST RECENTLY CREATED
-3 3RD MOST RECENTLY CREATED
. .
. .
SINCE GENERATION LEVELS ARE NEGATIVE, THIS DOCUMENT ASSUMES
THE CONVENTION THAT -2 IS "BELOW" -1, -3 IS "ABOVE" -5, ETC.
GENERATION LEVELS ARE ALWAYS CONTIGUOUSLY OCCUPIED, BEGINING
WITH -1 AND GOING DOWN THROUGH THE NUMBER OF EXISTING
GENERATIONS.
D. GENERATION COUNT (GEN=)
EACH TIME A GENERATION IS CREATED (MOUNTED FOR OUTPUT)
A GENERATION COUNT FOR THAT VID IS INCREMENTED AND ASSIGNED
TO THAT GENERATION. THE GENERATION COUNT IS A POSITIVE
NUMBER HAVING THE FOLLOWING MEANINGS:
GENERATION COUNT MEANING
1 1ST GENERATION CREATED
2 2ND GENERATION CREATED
3 3RD GENERATION CREATED
. .
. .
DTAPE WILL RESET THE GENERATION COUNT TO 1 WITH THE NEXT
CREATION AFTER 9999.
DTAPE DISPLAYS THE GENERATION LEVEL AND COUNT IN THE FORMAT
-L(C) WHERE "L" IS THE LEVEL AND "C" IS THE COUNT.
E. RETENTION CODE (RCD=)
EACH VID HAS A RETENTION CODE FOR DETERMINING WHAT
RETENTION DATE TO GIVE EACH NEW GENERATION. IT IS
A NUMERIC FIELD WHOSE VALUES HAVE THE FOLLOWING MEANINGS:
RETENTION CODE MEANING
-<INTEGER> KEEP <INTEGER> GENERATIONS
0 ILLEGAL VALUE
YYMMDD KEEP UNTIL AFTER THIS DATE
YY0000 KEEP YY YEARS
00MM00 KEEP MM MONTHS
0000DD KEEP DD DAYS
F. RETENTION DATE (RDT=)
EACH GENERATION MOUNTED FOR OUTPUT IS GIVEN A RETENTION
DATE AS FOLLOWS:
1. IF THE RETENTION CODE IS NEGATIVE, 999999 IS ASSIGNED.
2. IF THE RETENTION CODE IS POSITIVE, A RETENTION DATE
IS CALCULATED.
THE "SCRATCH EXPIRED" COMMAND WILL RETURN TO THE APPROPRIATE
SCRATCH VID, TAPES IN GENERATIONS:
1. HAVING RETENTION DATES LESS THAN TODAY'S DATE OR
2. AT GENERATION LEVELS BELOW THAT SPECIFIED BY A
NEGATIVE RETENTION CODE.
USING DTAPE:
A. GENERAL
WHEN DTAPE REQUIRES CONTROL INFORMATION, IT DISPLAYS
"XXX=" WHERE XXX IS A MNEMONIC CODE INDICATING WHAT IS
REQUIRED. THE FIRST MNEMONIC IS "CMD=" WHICH MEANS A
COMMAND IS REQUIRED. AFTER ACCEPTING THE COMMAND, DTAPE
SIMILARLY ACCEPTS ALL PARAMETERS REQUIRED BY THE SPECIFIED
COMMAND. IT THEN PERFORMS THE COMMAND, DISPLAYS "CMD="
AND WAITS FOR THE NEXT COMMAND.
THE ALTMODE, INSTEAD OF THE CR, MAY BE USED TO TERMINATE
INPUTS SO THAT COMMAND DATA WILL BE STRUNG OUT HORIZONTALLY.
ONLY THE FIRST THREE CHARACTERS OF A COMMAND ARE REQUIRED.
THE "EXIT" COMMAND MAY BE USED TO RETURN CONTROL
TO THE MONITOR.
USERS SHOULD NEVER-NEVER-NEVER DO A ^C EXIT EXCEPT WHEN
DTAPE IS REQUESTING A COMMAND (CMD=) OR A PARAMETER (E.G. GEN=).
A ^C AT OTHER TIMES MAY LEAVE THE DTAPE FILES BOTCHED UP. TO KEEP
THIS KIND OF PROBLEM UNDER CONTROL, ALL COMMANDS WHICH UPDATE
THE DTAPE FILES SET A FLAG ASSOCIATED WITH THE VID BEING AFFECTED.
THE FLAG IS SET AFTER ALL NECESSARY PARAMETERS HAVE BEEN ENTERED AND
CLEARED WHEN THE COMMAND HAS BEEN COMPLETELY EXECUTED. IF THE
SYSTEM CRASHES (OR A ^C^C IS ENTERED) BEFORE THE COMMAND IS
COMPLETED, THE VID AFFECTED REMAINS FLAGGED.
ANY FURTHER UPDATE-TYPE COMMANDS AGAINST THAT VID WILL BE LOCKED
OUT PRODUCING THE ERROR MESSAGE:
"?LAST <CMD> COMMAND INCOMPLETE ON VID <VID>"
TO CLEAR THIS FLAG, TYPE THE VID IN QUESTION ON THE TTY.
AS DTAPE TYPES THE VID IT WILL CHECK FOR ANY INCONSISTENCIES
IN THE FILES. IF THE FLAG WAS SET AND THE FILES ARE OK,
IT WILL CLEAR THE FLAG AUTOMATICALLY. HOWEVER IF THE FILES
ARE BOTCHED UP, THE VID WILL REMAIN LOCKED UP, MAKING IT NECESSARY TO
RELOAD THE DTAPE FILES (DTAPE.VOL, DTAPE.VID, DTAPE.IDX)
FROM THE LATEST FAILSAFE TAPE.
B. COMMANDS
ADD - ADDS NEW VOLUMES TO THE SCRATCH VID'S OR NEW VID'S
TO THE SYSTEM.
TO ADD NEW VOLUMES TO A SCRATCH VID:
.RUN DTAPE
CMD=ADD
WHT=SCRATCH
SIZ=1200FT
DIS=-1 ADD EACH TAPE TO THE TOP OF VID 1200FT
VOL=786 *
VOL=787 *
VOL=790
? 790 ALREADY EXISTS
VOL=791 *
VOL=^C
* NEW 1200 FOOT TAPES MUST NOW BE VOLUME-LABELED
AND PLACED IN THE TAPE LIBRARY.
TO ADD A NEW VID TO THE SYSTEM:
.RUN DTAPE
CMD=ADD
WHT=VID
VID=GS1075
RCD=-5 KEEP MOST RECENT 5 GENERATIONS
RPG=2 2 REELS PER GENERATION WHEN MOUNTING SCRATCHES
MRS=0600FT MIN-REEL-SIZE WHEN MOUNTING SCRATCHES
CHANGE - CHANGES VOLUME NUMBERS, VID'S, RETENTION CODES,
RETENTION DATES AND RPG'S.
TO CHANGE VOLUME 278 TO 591 LEAVING 278 AN UNUSED NUMBER:
.RUN DTAPE
CMD=CHANGE
WHT=VOLUME
VOL=278
NEW=591
REEL 278 MUST NOW BE VOLUME-LABELED 591 AND PLACED
IN LOCATION 591 IN THE TAPE LIBRARY
TO CHANGE VID GS1075 TO GS10:
CMD=CHANGE
WHT=VID
VID=GS1075
NEW=GS10
TO CHANGE THE RETENTION CODE FOR GS10 SO TAPES
WILL BE KEPT 90 DAYS:
CMD=CHANGE
WHT=RCD
VID=GS10
NEW=000090
TO CHANGE THE RETENTION DATE FOR THE 82ND
GENERATION OF GS10:
CMD=CHANGE
WHT=RDT
VID=GS10
GEN=82
NEW=730628
TO CHANGE REELS-PER-GEN FOR GS10 SO 3 SCRATCH REELS WILL
BE SELECTED WHEN A MOUNT CALLS FOR A SCRATCH:
CMD=CHANGE
WHT=RPG
VID=GS10
NEW=3
TO CHANGE MIN-REEL-SIZE FOR GS10 SO DTAPE WILL
BEGIN LOOKING IN THE 1200FT SCRATCH VID WHEN SCRATCH
TAPE(S) IS (ARE) REQUIRED:
CMD=CHANGE
WHT=MRS
VID=GS10
NEW=1200FT
DELETE - DELETES SCRATCH TAPES AND NULL VID'S FROM THE SYSTEM.
TO DELETE SCRATCH TAPE 221 FROM THE SYSTEM:
CMD=DELETE
WHT=SCRATCH
VOL=221
TO DELETE GS10 FROM THE SYSTEM:
CMD=DELETE
WHT=VID
VID=GS20
? GS20 NOT EMPTY
CMD=DELETE
WHT=VID
VID=GS10
ASSIGN - ASSIGNS REELS TO THE SPECIFIED VID AND GENERATION.
IF THE GENERATION ALREADY HAS N REELS, THE NEW ONE
BECOMES N+1. IF NO SUCH GENERATION EXISTS, A NEW
GENERATION IS CREATED BELOW THE LOWEST EXISTING
GENDRATION.
TO ASSIGN VOLUME 1235 TO GS10 LEVEL -2:
CMD=ASSIGN
WHT=VOLUME
VOL=1235 MUST BE A SCRATCH TAPE
VID=GS10
GEN=-2
TO ASSIGN A 1200 FOOT SCRATCH TO GS10 735TH GENERATION:
CMD=ASSIGN
WHT=SCRATCH
SIZ=1200FT VID OF THE 1200 FOOT SCRATCH POOL
VID=GS10
GEN=735
SCRATCH - RETURNS THE SPECIFIED TAPES TO THE
APPROPRIATE SCRATCH VID'S.
TO SCRATCH THE LAST REEL FROM GD10 GENERATION LEVEL -3:
CMD=SCRATCH
WHT=REEL
VID=GS10
GEN=-3
TO SCRATCH THE ENTIRE -5 GENERATION LEVEL:
CMD=SCRATCH
WHT=GENERATION
VID=GS10
GEN=-5
TO SCRATCH ALL EXPIRED GENERATIONS IN THE SYSTEM:
CMD=SCRATCH
WHT=EXPIRED AS A PRECAUTION, THIS KIND OF SCRATCH
MUST BE PRECEEDED BY A TYPE-OUT OF ALL
EXPIRED TAPES
WHENEVER TAPES ARE SCRATCHED, THEIR VID-LABELS MUST BE
REMOVED.
SWAP - SWAPS THE ASSIGNMENT OF ANY TWO VOLUMES IN THE SYSTEM.
TO SWAP VOLUME 19 WITH 1573:
CMD=SWAP
VOL=19
*** VID=GS10 GEN=-12 REEL=1
VOL=1573
*** VID=PR15 GEN=-1 REEL=5
CONTINUE?=YES
*** SWAPPED ***
TYPE - TYPES A DISPLAY OF THE SPECIFIED INFORMATION
ON THE TTY.
TO TYPE THE STATUS OF VOLUME 235:
CMD=TYPE
WHT=VOLUME
VOL=235
VID GENERATION ***CREATED****BY*** RDT REEL
GS10 -3(0217) 73/04/15 17:30 JOB1 73/07/15 3
TO TYPE THE STATUS OF VID GS10:
CMD=TYPE
WHT=VID
VID=GS10
RCD: -6
RPG: 2
MRS: 1200FT
VOL GENERATION ***CREATED******BY*** RDT
0023 -1(0002) 73/12/15 15:32 STEP2 99/99/99
0024
0027 -2(0001) 73/05/03 09:23 STEP2 99/99/99
0026
TO TYPE SCRATCH STATISTICS:
CMD=TYPE
WHT=SCRATCH
VID NUMBER
0300FT 0
0600FT 13
1200FT 91
2400FT 146
TO TYPE EXPIRED TAPES IN GS10:
CMD=TYPE
WHT=EXPIRED
VID=GS10
DISPLAY IS SIMILAR TO VID TYPE-OUT
TO TYPE ALL EXPIRED TAPES:
CMD=TYPE
WHT=EXPIRED
VID=ALL
REPORT - CREATES A REPORT FILE NAMED DTAPE.LPT
SHOWING THE COMPLETE VOLUME STATUS
AND VID STATUS OF THE SYSTEM:
CATALOG - CATALOGS A SELECTED GENERATION OF A VID AT
THE SPECIFIED GENERATION LEVEL.
WHEN DTAPE CATALOGS A GENERATION, TWO PARAMETERS ARE
REQUIRED; THEY ARE GENERATION (GEN=) AND DISPOSITION (DIS=).
THE GENERATION PARAMETER IS USED FOR FINDING THE GENERATION
TO BE CATALOGED; AND THE DISPOSITION PARAMETER SPECIFIES THE
LEVEL AT WHICH IT IS TO BE CATALOGED. THE GENERATION
PARAMETER MAY BE A GENERATION LEVEL OR COUNT. THE DISPOSITION
PARAMETER MUST BE ZERO OR A GENERATION LEVEL.
WHEN THE DISPOSITION SPECIFIES AN OCCUPIED LEVEL, GENERATIONS
AT THAT LEVEL AND BELOW ARE SHIFTED DOWN ONE LEVEL AND THE
CATALOGED GENERATION IS INSERTED AT THE VACATED LEVEL.
WHEN THE DISPOSITION SPECIFIES A GENERATION LEVEL BELOW
THOSE OCCUPIED, THE CATALOGED GENERATION IS PLACED IMMEDIATELY
BELOW THE LOWEST OCCUPIED LEVEL.
"BEFORE" PLACING THE CATALOGED GENERATION AT ITS NEW LEVEL,
ITS OLD LEVEL IS DELETED, CAUSING ALL GENERATIONS BELOW
TO BE SHIFTED UP ONE LEVEL. THE DISPOSITION PARAMETER
IS THEN USED TO LOCATE THE NEW LEVEL. THEREFORE, WHEN
THE CATALOGING IS FINISHED, THE CATALOGED GENERATION
WILL REMAIN AT THE LEVEL SPECIFIED BY THE DISPOSITION
PARAMETER (UNLESS, OF COURSE, IT POINTS BELOW THE
LOWEST OCCUPIED LEVEL).
TO CATALOG GS10 -2 AT -4:
CMD=CATALOG BEFORE AFTER
VID=GS10 LEVEL VOL LEVEL VOL
GEN=-2 -1 101 -1 101
DIS=-4 -2 102 -2 103
-3 103 -3 104
-4 104 -4 102
-5 105 -5 105
TO CATALOG GS10 -3 AT -1:
CMD=CATALOG BEFORE AFTER
VID=GS10 LEVEL VOL LEVEL VOL
GEN=-3 -1 101 -1 103
DIS=-1 -2 102 -2 101
-3 103 -3 102
MOUNT - PERFORMS THE FOLLOWING FUNCTIONS:
1. CREATES A COMMAND FILE NAMED <LOGICAL DEV>.CMD
FOR USE BY:
A. A SUBSEQUENT "MOUNT @<LOGICAL DEV>.CMD".
B. ANY PROGRAM WHICH INCLUDES THE VOLUME NUMBER
IN ITS VALUE OF ID FOR LABEL CHECKING.
2. IF THE MOUNT IS FOR OUTPUT, THE CURRENT DATE IS
IS RECORDED AS THE CREATION DATE AND THE CURRENT
TIME IS RECORDED AS THE CREATION TIME. ALSO THE
THE GENERATION COUNT FOR THAT VID IS INCREMENTED
AND APPLIED TO THAT GENERATION.
3. CATALOGS THE "MOUNTED" GENERATION AT THE SPECIFIED
LEVEL. IF DIS=0, THE GENERATION IS LEFT AT ITS
ORIGINAL POSITION; THIS ALLOWS ACCESSING THE N-TH
GENERATION WITHOUT KNOWING ITS LEVEL AND WITHOUT
DISTURBING IT.
THE GENERATION COUNT IS IN REALITY
A COUNT OF THE NUMBER OF OUTPUT MOUNT COMMANDS PERFORMED
ON A GIVEN VID BY DTAPE.
IF THE GENERATION PARAMETER HAS A VALUE OF 0, SCRATCH
TAPES WILL BE SELECTED AND ASSIGNED TO A NEW GENERATION.
THE NEW GENERATION WILL BE CATALOGED AS SPECIFIED BY
THE DISPOSITION PARAMETER. THE NUMBER OF TAPES SELECTED
DEPENDS ON THE REELS-PER-GENERATION (RPG=) FOR THAT
VID. DTAPE WILL LOOK FIRST IN THE SCRATCH VID
SPECIFIED BY THE MIN-REEL-SIZE PARAMETER. IF THAT
SCRATCH VID CANNOT SATISFY THE REQUIREMENT,
DTAPE WILL LOOK IN THE NEXT SIZE LARGER SCRATCH VID,
AND SO ON THRU 2400FT.
WHEN SCRATCHES ARE MOUNTED FOR OUTPUT, IT IS THE
OPERATOR'S RESPONSIBILITY TO LABEL THEM WITH VID-LABELS.
SINCE THE VID PORTION OF THE MOUNT COMMAND FILE CONTAINS
ONLY VOLUME NUMBERS, THE OPERATOR MUST BE INFORMED VIA
THE "SEND" MONITOR COMMAND OF ANY INFORMATION REQUIRED
ON THE NEW VID-LABEL.
TO MOUNT THE 91ST GENERATION OF GS10 FOR INPUT
ON LOGICAL DEVICE "MASTIN" AND KEEP IT AT ITS CURRENT
LEVEL:
.RUN DTAPE
CMD=MOUNT
LDV=MASTIN
VID=GS10
GEN=91
DIS=0
USE=INPUT
WHO=GS1080
CMD=EXIT
.MOUNT @MASTIN.CMD
MASTIN.CMD HAS THE FOLLOWING FORMAT:
MTA MASTIN /VID:0128-1132 /WLOCK
TO MOUNT GS10 -1 FOR INPUT ON MASTIN AND GS10 -3 FOR
OUTPUT ON MSTOUT AND TO CATALOG -3 AS -1:
.RUN DTAPE
CMD=MOUNT
LDV=MASTIN
VID=GS10
GEN=-1
DIS=0
USE=INPUT
WHO=GS1080
CMD=MOUNT
LDV=MSTOUT
VID=GS10
GEN=-3
DIS=-1
USE=OUTPUT
WHO=GS1080
CMD=EXIT
.MOUNT @MASTIN.CMD
.MOUNT @MSTOUT.CMD
TO MOUNT SCRATCHES FOR OUTPUT AS THE -1 GENERATION LEVEL
OF GS10:
.RUN DTAPE
CMD=MOUNT
LDV=TAPOUT
VID=GS10
GEN=0
DIS=-1
USE=OUTPUT
WHO=GS80
CMD=EXIT
.MOUNT @TAPOUT.CMD
EXIT - TERMINATES THE CURRENT DTAPE RUN.
START-UP PROCEDURE:
1. CREATE DTAPE.VOL FILE BY RUNNING DTAPE1.
2. CREATE DTAPE.VID AND DTAPE.IDX FILES BY RUNNING ISAM.
A. INPUT NULL SEQUENTIAL FILE.
B. DATA FILE: SIXBIT
C. MAX REC SIZE: 66
D. KEY DESCR: X1.10
E. RECS PER OUTPUT BLK: 10
F. OTHER PARAMETERS DEPEND ON SIZE OF TAPE LIBRARY
AND ANTICIPATED ACTIVITY.
3. ADD EACH OF THE SCHRATCH VIDS (0300FT, 0600FT, 1200FT, 2400FT).
E.G. CMD=ADD
WHT=VID
VID=0300FT
RCD=-9999
RPG=1
MRS=0300FT
4. ADD TAPES TO SCRATCH POOLS.
E.G. CMD=ADD
WHT=SCR
SIZ=0300FT
DIS=-99
VOL= <FIRST VOLUME NUMBER>
VOL= <NEXT VOLUME NUMBER>
.
.
.
.