Ultrix 4.1 dd gives meaningless "Error 0" messages

[Ian! D. Allen [CGL]]

    # dd if=ultrix4.1src.tar.Z of=/dev/nrmt0h bs=64k
    write: Error 0
    8+0 records in
    0+0 records out
    29464 Exit 255             dd if=ultrix4.1src.tar.Z of=/dev/nrmt0h bs=64k
    # mt rew
    # dd if=ultrix4.1src.tar.Z of=/dev/nrmt0h bs=63k
    /* this one worked */

I presume something in the driver is limiting the size of the records
that can be written to the TK70 tape drive, but "Error 0" is just not a
useful error message.  Even "I/O Error" would be better than "Error 0".
-- 
-IAN! (Ian! D. Allen) idallen at watcgl.uwaterloo.ca idallen at watcgl.waterloo.edu
 [129.97.128.64]  Computer Graphics Lab/University of Waterloo/Ontario/Canada