ingea@IFI.UIO.NO (Inge Arnesen) (11/13/90)
While going through RFC 1179 (thanks to L.J. McLaughlin for writing it!),
I've stumbled across a few points I need some help with:
1) In section 3.1 in RFC1179, it says:
"The source port must be in the range 721 to 731 inclusive."
I've looked through a two different implementations, and I cannot find
any reference to specific client port numbers, expect that they must be
in the reserved range (below 1024). RFC1060 does not list these port
numbers as reserved for LPD client. Is this number range reserved for
LPD ? Are checks made by different LPD's to verify client source number?
2) In section 6.3 in 1179, it says:
"The total number of bytes in the stream may be sent as the first operand,
otherwise the field should be cleared to 0"
Note: The receive data file command.
Once again I've looked at source code and done some testing, and I cannot
understand the perpose of setting the "number of bytes" field to zero.
If this this field is cleared, the LPD server part assumes that the data
file has a zero length (as far as I can see from the BSD source and some
other implementations).
Are there implementations around that allow the client side to specify
zero data file length to mean unknown length ? In that case, how does
the server side know when the whole data file has been transfered ?
If the file is pure ASCII it poses no problem, since the terminating
NULL char can act as an EOF marker, but what about non-ASCII files ?
Inge (BoB) { ingea@ifi.uio.no }
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== Inge Arnesen, University of Oslo, Norway. ==
== ==