From: Volkan YAZICI <volkan.yazici@gmail.com>
To: PostgreSQL Interfaces <pgsql-interfaces@postgresql.org>
Subject: Network Byte Order Coercion
Date: Mon, 16 May 2005 13:12:37 +0300
Message-ID: <7104a73705051603121f1c35ab@mail.gmail.com> (raw)
Hi,
In libpq example program 3 (testlibpq3.c), an int4 field is converted
to host byte order:
{{{
/* Get the field values (we ignore possibility they are null!) */
iptr = PQgetvalue(res, i, i_fnum);
/*
* The binary representation of INT4 is in network byte order,
* which we'd better coerce to the local byte order.
*/
ival = ntohl(*((uint32_t *) iptr));
}}}
(As I saw while reading "An Essay on Endian Order" [1]) I'm not so
familiar with byte orders, but what's the point of coercion in here?
Should we do it in every integer field we retrieved? What's the
[dis]advantages of this? I'd be so appreciated for any explanation.
[1] http://www.cs.umass.edu/~verts/cs32/endian.html
Regards.
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-interfaces@postgresql.org
Cc: volkan.yazici@gmail.com
Subject: Re: Network Byte Order Coercion
In-Reply-To: <7104a73705051603121f1c35ab@mail.gmail.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox