bobl@zeus.UUCP (Bob Lewis) (08/14/84)
I have a tape produced by a Data General machine running RDOS. The tape was made by the standard DG "DUMP" program. The tape seems to be a concatenation of individual files, but I can't determine the individual format of each file. There is, of course, "NUXI" scrambling, but what I'm uncertain about is where the timestamp and byte (or whatever) counts are supposed to be in the first place. Can anyone out there explain the format or (hope hope) provide or point to an existing conversion program? Replies by net mail, please. - Bob Lewis ...!tektronix!teklds!bobl
jackm@ARDC.ARPA (08/24/84)
From: Jack Moskowitz (PAD) <jackm@ARDC.ARPA>
>From a very old DG RDOS Reference Manual.
Dump files are formatted into the following types of blocks:
1) Name blocks - 377
2) Data blocks - 376
3) ERror blocks - 375
4) End blocks - 374
5) Time blocks - 373
6) Link data blocks - 372
These formats are given in the following illustrations:
1) Name block
block id 1 byte 377
attributes 2 bytes
No of contiguous blocks only if contiguous characteristic set 2 bytes
filename 10 bytes
terminator (null)
2) data block
block id 1 byte 376
byte count 2 bytes
checksum (wc mod 2 + tot contents all full words) 2 bytes
data n bytes
no terminator
3) error block
block id 1 byte 375
4) end block
block id 1 byte 374
5) time block (follows name block wxcept on links)
block id 1 byte 373
julian day last access (opened) since 1/1/68 2 bytes
julian day created 2 bytes
time created left byte = hour, right byte = min created 2 bytes
no terminator
6) link data block (follows name block on link)
block id 1 byte 372
alternate dir name(if any) followed by null variable bytes
link alias name(if any) followed by null variable bytes
Hope this helps
Jack Moskowitz <jackm@ardc>
AMCCOM
Dover, New Jersey 07801