[mod.computers.vax] VMS processing of IBM tapes

"Bruce_G._Kahler.rochX2"@XEROX.COM (10/30/86)

Any suggestions of how to read/write tapes under VMS in the EBCDIC character set?

McGuire_Ed@GRINNELL.MAILNET (11/04/86)

There are two approaches to reading EBCDIC coded tapes.  Either involves
writing some code.  You can write a program that reads tapes directly, or
you can use VMS to transfer the files to disk and write a program that
converts the files from EBCDIC to ASCII coding on disk.

To copy any foreign file from tape to disk, mount the tape /FOREIGN, and
execute COPY commands such as COPY MUA0: FILE1.DAT, COPY MUA0: FILE2.DAT,
etc.  COPY knows to stop at end-of-file marks.  When you are done, you
will have files in your account that contain the EBCDIC-coded information.
If the tape was written with standard IBM labels, then some of the files
will contain the label information, and some will contain data files.

In a program to convert from EBCDIC to ASCII, you can use the library
routine LIB$TRA_EBC_ASC, which will do the mapping of EBCDIC to ASCII
codes for you.  See the documentation.

We use the AVATU program (from a DECUS tape) when we need to read (or write)
EBCDIC tapes with standard IBM labels.  Undoubtedly, other INFO-VAX readers
can suggest other programs that have already been written to do certain
other kinds of EBCDIC <-> ASCII conversions.

cetron@UTAH-CS.ARPA (Edward J Cetron) (11/06/86)

	Another solution is to find an RSX system which will do the 
EBCDIC -> ASCII conversion automatically....and have it either rewrite
the tape for the vax, or as I do, decnet the results over to the vax...
In fact, the RSX manual set even includes a step by step example on how
to read IBM  EBCDIC tapes...

-ed