[comp.mail.uucp] HDB and junk in files

dg@lakart.UUCP (David Goodenough) (06/19/89)

Yet another question spawned by a problem with my new UUCP system
talking to HDB - this is a hex dump of a file received:

Sector 0000 of B:D-E0-9D7.USR

0000:  67 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00   g...............
0010:  00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00   ................
0020:  00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00   ................
0030:  00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00   ................
0040:  46 72 6f 6d 20 64 61 76-65 67 20 20 53 61 74 20   From daveg  Sat 
0050:  4a 75 6e 20 31 37 20 32-32 3a 33 34 3a 35 35 20   Jun 17 22:34:55 
0060:  31 39 38 39 20 72 65 6d-6f 74 65 20 66 72 6f 6d   1989 remote from
0070:  20 75 73 6f 75 72 63 65-0a 52 65 63 65 69 76 65    usource.Receive

The rest is not important - the question I have is:

What gives with the extra junk packet sent before the file transmission
really got under way?? (i.e. a 'g' and 63 nulls) - does HDB add some
extra crud that isn't documented? and if so can someone please post
some form of information about it. This is from a Xenix SCO system
running a version of HDB - standard BSD UUCP (both V4.2 and 4.3) don't
do this.

Or is this just a bug in HDB?

Enquiring minds want to know?????? Also I want to know how I can tell
the difference between junk and real binary data when I'm receiving
grafix pixel information - I can think of several ways of discarding
the errant packet, but all of them run a risk of discarding valid
data when a binary file transfer is in progress - and I plan to use
this to dial in to remote access sites and UUCP out compressed files,
so I need binary transmission to work right.
-- 
	dg@lakart.UUCP - David Goodenough		+---+
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