[Info-vax] Question about checksum in BACKUP block headers

[Anton Lavrentiev]

> What version of RSTS? 

I have a few backups, both RSTS and VMS, and they share the same BACKUP format.
(I believe RSTS is 10.1, so pretty advanced.)

I noticed that RSTS backups do not use whole-block CRCs, only block header checksums.  VMS ones do, and they look like CRC-32s, but so far I wasn't able to figure out, which part of the data block they are summing.