Hi all, I have a question I hope someone can help me with:
I'm doing some communication over a socket, and have need to send
and receive values of type double. I'm doing everything in terms
of single byte reads and writes to the socket, so what I need to do
is take the individual bytes I receive, that represent a double, and
actually turn them into a double. This I'm struggling to figure
out.
I can easily combine the bytes into a container of some sort
(like say a long) that has the same bit pattern as the double
I want. For example, I can get to the point of having a long
that looks like 0001 1110 1000 0000 for 7.5d. But I can't
seem to get that into a double. A simple cast doesn't appear
to work, and I'm not sure what else to try.
Any help or ideas is greatly appreciated.
Thanks,
Phillip Rhodes
--
North Carolina - First In Freedom
Free America - Vote Libertarian www.lp.org
Jul 23 '05
15  6732 
Greg wrote:
[snip]
It's also reinventing the wheel. For sending data types and data
structures over a network, by the far the easiest and most
interoperable approach would be to use ASN.1 notation and a BER library
(Basic Encoding Rules) to encode and decode the data on both ends of
the connection. Not only do well-debugged, freely available
implementations exist on every major platform, but the BER notation
being self-describing is quite robust. It is the data encoding format
used by dozens of standards and innumerable RFCs.
[snip]
Could you provide some links to Linux Open Source libs req'd to
do the job - libs to be linked to a C++ app.
Google hasn't helped much with this.
Thanks,
Larry
Greg wrote: It's also reinventing the wheel. For sending data types and data
structures over a network, by the far the easiest and most
interoperable approach would be to use ASN.1 notation and a BER library
(Basic Encoding Rules) to encode and decode the data on both ends of
the connection. Not only do well-debugged, freely available
implementations exist on every major platform, but the BER notation
being self-describing is quite robust. It is the data encoding format
used by dozens of standards and innumerable RFCs.
Hmmm... I have to admit, I'm not very familiar with ASN.1. I'll look
into it, but I suspect it may be overkill for what I'm trying to do.
I'll definitely look it up and take a look though.
TTYL,
Phil
--
North Carolina - First In Freedom
Free America - Vote Libertarian www.lp.org
Greg schreef: It's also reinventing the wheel. For sending data types and data
structures over a network, by the far the easiest and most
interoperable approach would be to use ASN.1 notation and a BER library
(Basic Encoding Rules)
Even easier than text? I mean, reading and writing "1.0" is very easy.
Best of all, if it doesn't work you can look at the raw bits and
understand them. Try that with ASN.1
There's a good reason most RFCs use text and not ASN.1
HTH,
Michiel Saltres
Text is a very fine thing. However, you might lose precision while
converting back and forth the decimal-based text format.
li*****@gmail.c om wrote: http://lionet.info/asn1c is a free ASN.1 compiler.
Awesome, thanks for the link. I'm not 100% sure
I need ASN.1 for the problem I'm working on right now,
but it definitely looks like something I should get
familiar with. I'll definitely be downloading
and looking at this.
Thanks again,
Phillip
--
North Carolina - First In Freedom
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