vax/unix to vax/vms

[eric]

> Is there any way I can create a tape on a vax11/780 running UNIX*
> that can be read into a vax11/780 running VMS?  What the UNIX tape needs is
> to have a FILES-11 label put on it, but I can't figure out how to do this.
> Anyone want to pick up this challenge?
> 

I don't know where this myth started that tapes need to
be labeled to be read by VMS, but I will say so again:

	A tape written with the raw magtape interface is
directly readable on VMS if it is mounted as an unlabeled (foreign)
tape.  Each write(2) writes one block on the tape.  Each block on
a tape corresponds to one record.  A record is the entity
that is read with a FORTRAN READ statement for instance.
In addition, the COPY command transfers each tape block to
a disk file record, so the tape can be trivially copied to
disk and operated on from there.  Any program that can read
the tape, will behave identically when using the disk file.

When mounting the tape, the BLOCKSIZE specifier gives the maximum
number of bytes written in any one block.
If you do not use the raw magtape interface, then each block
on the tape will be 512 or 1024 bytes long depending on which
system you run.

There.

Now to answer the original question:  There are several people
around who have ANSI tape labelers that run on UNIX.  Other
useful things:  I have a tar that runs on VMS.  Ascii text
transfers fine, binary files require care.

					Eric Stern
					stern at bnl.arpa
					...!philabs!sbcs!stern