bernie@UMBC2.UMD.EDU ("Bernie Duffy") (01/04/87)
This listing is a log of what it took to put a 2nd TM (tape mark) on the
end of a tape that is missing it. The tapes came from an IBM (we got to
convert their data some day) and didn't have the required two tape marks that
signifies the end of a volume (physical tape reel). The format of the tapes
were the ANSI standard, but missing the double TM (EOV) that comes after the
physical tape mark (the piece of foil) and the 'End of Volume' block. The
actual end of tape is denoted by 2 consecutive TMs and the physical TM (foil)
doesn't do much (but is very useful in repairing this condition). The data
on the tapes was one 'file' that spanned 11 volumes and we had to do this
procedure for each of the tapes. We're running V4.4!
I hope this will save someone the time I had to spend getting the answer
from DEC and finding out what the problem was.
Bernie Duffy
Academic Computing: Library Room L005
University of Maryland, Baltimore County (U.M.B.C.)
5401 Wilkens Avenue
Catonsville, MD 21228
BITNET: BERNIE@UMBC2
ARPAnet: BERNIE@UMBC2.UMD.EDU
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$!
$! MOUNT and advance the tape to it's end....
$!
$ mount/for tape0:
%MOUNT-I-MOUNTED, 000005 mounted on _HSC014$MUA0:
$
$ !
$ ! first 'END OF FILE' is due to the TM (tape mark) in one of the HDR block
$ !
$ set magtape/skip=blocks:10000 tape0:
%SET-E-NOTSET, error modifying TAPE0:
-SYSTEM-W-ENDOFFILE, end of file
$ !
$ !
$ ! skip... with 4 or so SET MAG... to the PHYSICAL TM
$ !
$ set magtape/skip=blocks:10000 tape0: ! in my case if I tried to use more
$ set magtape/skip=blocks:10000 tape0: ! than 10000 (like 40000) the tape
$ set magtape/skip=blocks:10000 tape0: ! would rewind or not move. We have
$ set magtape/skip=blocks:10000 tape0: ! TA78 (& TU78)s on a HSC50 V2.5
$ set magtape/skip=blocks:10000 tape0:
%SET-E-NOTSET, error modifying TAPE0:
-SYSTEM-W-ENDOFFILE, end of file
$
$ ! now the tape is positioned at the physical tape mark....
$ !... dump out the last block which contains the EOV (end of volume data)
$ ! (if you don't specify /BLOCKS=COUNT:1 when you only have one TM the
$ ! tape will spin off the original reel... a bit awkward to reload )
$
$ dump /blocks=count:1 tape0:
Dump of device HSC014$MUA0: on 29-DEC-1986 18:24:49.76
Block number 1 (00000001), 80 (0050) bytes
4F464552 2E454C49 4644454D 31564F45 EOV1MEDFILE.REFO 000000
30353030 30313030 30303020 54414D52 RMAT 00000100050 000010
20323533 36382031 30313030 30313030 001000101 86352 000020
20202020 33303832 34302032 35333638 86352 042803 000030
20202020 20202020 20202020 20202020 000040
$
$ ! set the EOV1 at the beginning of the blocks' data... after
$ ! this block there is suppose to be 2 TMs which mark the end of this tape.
$ ! since there is only one... (the one was used the end of block marker)
$
$ ! let's put on 2 to be safe ...
$
$ set magtape tape0:/end_of_file
%SET-E-NOTSET, error modifying TAPE0:
-SYSTEM-F-NOPRIV, no privilege for attempted operation
$ !... opps.. need privs. probably LOG_IO
$
$ set proc/priv=log_io
$
$ set proc/priv=log_io
$ !... opps.. need privs. probably LOG_IO
$
$ set magtape tape0:/end_of_file ! try again
%SET-E-NOTSET, error modifying TAPE0:
-SYSTEM-W-ENDOFTAPE, end of tape
$
$ set magtape tape0:/end_of_file ! ... ignore the errors watch the tape move
%SET-E-NOTSET, error modifying TAPE0:
-SYSTEM-W-ENDOFTAPE, end of tape
$
$ ! if it move you're okay.
$
$ ! now rewind it and check your work (all this is with V4.4 VMS)
$
$ SET MAGTAPE/REWIND TAPE0:
$
$ ! GO THROUGH THE 'skip' sequence again to verify two TM (*** end of file ***)
$ ! ...
$ set magtape tape0:/skip=blocks:10000
%SET-E-NOTSET, error modifying TAPE0:
-SYSTEM-W-ENDOFFILE, end of file
$ set magtape tape0:/skip=blocks:10000
$ set magtape tape0:/skip=blocks:10000
$ set magtape tape0:/skip=blocks:10000
$ set magtape tape0:/skip=blocks:10000
$ set magtape tape0:/skip=blocks:10000
%SET-E-NOTSET, error modifying TAPE0:
-SYSTEM-W-ENDOFFILE, end of file
$ !
$ ! verify via dump... (this dump with out the 2 TMs spins the tape off
$ ! the reel .... a pain to reload )
$ dump tape0:
Dump of device HSC014$MUA0: on 29-DEC-1986 18:38:46.46
Block number 1 (00000001), 80 (0050) bytes
4F464552 2E454C49 4644454D 31564F45 EOV1MEDFILE.REFO 000000
30353030 30313030 30303020 54414D52 RMAT 00000100050 000010
20323533 36382031 30313030 30313030 001000101 86352 000020
20202020 33303832 34302032 35333638 86352 042803 000030
20202020 20202020 20202020 20202020 000040
*** End of file ***
*** End of file ***
$ dismount tape0:
$
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