Re: directly serializing structs

From:

James Kanze <james.kanze@gmail.com>

Newsgroups:

comp.lang.c++

Date:

Thu, 28 Jun 2007 10:08:14 -0000

Message-ID:

<1183025294.315085.251560@n2g2000hse.googlegroups.com>

On Jun 27, 10:50 pm, "JohnQ" <johnqREMOVETHISprogram...@yahoo.com>
wrote:

"Dave Rahardja" <drahardja_atsign_pobox_dot_...@pobox.com> wrote in messa=

On Tue, 26 Jun 2007 03:30:54 -0500, "JohnQ"
<johnqREMOVETHISprogram...@yahoo.com> wrote:

"James Kanze" <james.ka...@gmail.com> wrote in message
news:1182688051.946308.66190@p77g2000hsh.googlegroups.com...
On Jun 23, 11:58 am, "JohnQ" <johnqREMOVETHISprogram...@yahoo.com>
wrote:

(Note too that "endianness" isn't a good word, since it suggests
two possible arrangements. At least three are widespread.)

But that one is called "middle ENDIAN" right? If so, that makes
"endianness"
seem OK.

I think the final takeaway of this thread may be this:
define your serialization schema down to the bit level, in a
separate document from your internal program design. Then,
provide an interface that allows you to serialize and
unserialize your internal data structures. Then, provide a
compiler/platform specific library to perform the
conversions. Then, replace or conditional-compile the
conversion library as needed as your program gets ported
from one compiler/platform to another.

If hardware and language vendors/developers could get their
acts together, think how much simpler it would be to develop
software.

I don't have any problems in that regard today.

"High level languages" that don't abstract away the hardware,
aren't!

But C++ does. And that's precisely what you're complaining
about; the fact that within a C++ program, there is no
endianness, so when you want to serialize, you have to introduce
it. C++ has abstracted away the hardware, and you don't know
how int's are represented on your machine. The external format,
however, has its requirements, since you transmit bytes, and not
ints.

With the exception of floating point, it's child's play, and
never represents more than two or three lines of code (in
applications which generally consist of hundreds of thousands of
lines, if not millions).

--
James Kanze (GABI Software) email:james.kanze@gmail.com
Conseils en informatique orient=E9e objet/
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