[VMS backup] tapes not copyable by dd???

[Jeffrey W Percival]

In article <11593 at bloom-beacon.MIT.EDU> scs at adam.pika.mit.edu (Steve Summit) writes:

>In article <184 at larry.sal.wisc.edu> jwp at larry.sal.wisc.edu (Jeffrey W Percival) writes:

>> (a detailed description of VMS backup tapes)

Thanks for the good description.  I knew about the multi-file format,
and have some more info on this problem:  when vmsbackup tries to read
the first 8192-byte record from file 2, read(2) returns a zero.  The
record is on the tape, because dd can retrieve it.

What could cause read(2) to return zero on a record that dd can find
on the tape?  Could this be related to the TK50 whirring back and
forth after just having read the file mark?
-- 
Jeff Percival (jwp at larry.sal.wisc.edu)