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The Question is: I'm very new to VMS How can I read information backed up on a magnetic tape? Is there a command for that? I want to see information stored on individual tapes. And also, how would I change inormation on forms or create new ones? HELP! The Answer is :
The two commands most commonly used to transfer data to or from magnetic
tape media are BACKUP and COPY.
For archival storage and for interchange with other OpenVMS systems, the
OpenVMS Wizard recommends BACKUP.
Most magnetic tape has a structure based on ANSI tape labeling standards.
ANSI labels are a set of predefined records written to the tape media,
these records provide host operating systems with information on the
contents and the structure of the data on the tape. A program can be
coded to write these ANSI records to the tape, or a system service such
as sys$init_vol() can be used, or the INITIALIZE command can be used.
Magnetic tape media can have a Files-11 structure layered onto the ANSI
records, meaning that commands such as DIRECTORY and COPY will work.
As a start:
$ MOUNT/OVERRIDE=IDENTIFICATION mmcu:
$ DIRECTORY mmcu:[000000]
$ DISMOUNT/NOUNLOAD mmcu:
Magnetic tape media can also have foreign-format structure. BACKUP uses
a foreign structure based on ANSI, as do various other utilities. As
OpenVMS can mount and access these tapes as "native" -- without using
/FOREIGN -- COPY and DIRECTORY can be used to view the contents of these
BACKUP tapes. That said, BACKUP and /FOREIGN should be used to read and
write these tapes.
To list the contents of the first BACKUP saveset located on a tape:
$ MOUNT/FOREIGN mmcu:
$ BACKUP mmcu:/SAVE/LIST
$ DISMOUNT/NOUNLOAD mmcu:
There are also utilities that do not use ANSI labeling structure. These
are not accessable via COPY and such and must be mounted /FOREIGN. The
contents are not accessable save via the application(s) that wrote the
data, or via tools such as DUMP.
For details on tape operations, please see the _OpenVMS User's Manual_,
_OpenVMS System Manager's Manual_, and _Guide to OpenVMS File Applications_
These manuals are available in hardcopy and are also accessable at:
http://www.openvms.digital.com:8000/
Since you are new to OpenVMS, please take the time to read the OpenVMS
User's Manual. In the specific case of this question, please start with:
http://www.openvms.digital.com:8000/72final/6489/6489pro_028.html#devices_ch
There are several different constructs refered to as "forms", ranging
from printer forms to FMS forms to DECforms forms, to forms from other
packages. Additional details will be required.
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