Reading BSD 4.3 tar tapes on System V

[gwyn at brl-smoke.UUCP]

In article <109 at amcad.UUCP> billb at amcad.UUCP (Bill Burton) writes:
>	We have a Burroughs XE-550 running CENTIX (System V) and have
>been unable to read tapes created with tar on a VAX BSD 4.3 system.
>	One other thing.  We could successfully unpack a tar archive
>created under BSD 4.3 and sent via uucp with our System V tar.

This makes it sound like the problem is in the magtape blocking.
Either your magtape drive can't handle the large blocksize used
(typically 10240 bytes per block), or your "tar" gets confused
by whatever blocksize it finds.  Older System V "tar"s are known
to have this problem.  Two alternative methods: (1) supply an
explicit "b" option, as in "tar xbf 20 /dev/rmt0", or (2) use "dd"
to buffer the tape blocking, as in "dd if=/dev/rmt0 ibs=20b|tar xf -".