From owner-freebsd-questions@FreeBSD.ORG  Wed Dec 10 16:51:12 2008
Return-Path: <owner-freebsd-questions@FreeBSD.ORG>
Delivered-To: Questions@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id D6CBD1065673
	for <Questions@freebsd.org>; Wed, 10 Dec 2008 16:51:12 +0000 (UTC)
	(envelope-from pdcvgmh@gmail.com)
Received: from mail-bw0-f14.google.com (mail-bw0-f14.google.com
	[209.85.218.14])
	by mx1.freebsd.org (Postfix) with ESMTP id 629B88FC2D
	for <Questions@freebsd.org>; Wed, 10 Dec 2008 16:51:11 +0000 (UTC)
	(envelope-from pdcvgmh@gmail.com)
Received: by bwz7 with SMTP id 7so895125bwz.19
	for <Questions@freebsd.org>; Wed, 10 Dec 2008 08:51:10 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma;
	h=domainkey-signature:received:received:message-id:date:from:to
	:subject:mime-version:content-type;
	bh=JTeFyO3QyS0eTVb0uiMegu2q9HaU39mP425UQwAHPYI=;
	b=WG5DJZFIQgXwpHE0m39ifPEch4MaeiRWlCY/gUVRCb48kt/t5DEpCcxrJLQ8HbqeHy
	pSjSrG42JF7SMhVwaumWFbQ8hH1Afh9VqQxaPDGoyjmXw34cHj0mdnw1uX2tFghlCSrt
	aW2CPKhpmUwXWP2mXdd7g74ZQm/Bx9prDnFMg=
DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma;
	h=message-id:date:from:to:subject:mime-version:content-type;
	b=dKac4TRo7/745Kv8U/0aB2o6f2HiuW1TZWyZiN7sC0+mdjdocukZu/g3of91AP2J40
	nR75uU+oul538e3Zg8LQqpGS5mg72yi72z8AypJvN/Lcq3UJUo6lkMBAUYlMHHyOng2J
	i7J76++D4rJWRZCZYPzvxD/TLpaU5wg+9FtoY=
Received: by 10.223.122.70 with SMTP id k6mr1585806far.26.1228925928851;
	Wed, 10 Dec 2008 08:18:48 -0800 (PST)
Received: by 10.223.119.6 with HTTP; Wed, 10 Dec 2008 08:18:48 -0800 (PST)
Message-ID: <b6db25ac0812100818w7ab98256qa5cc4054232e074d@mail.gmail.com>
Date: Wed, 10 Dec 2008 14:18:48 -0200
From: "pablo caballero" <pdcvgmh@gmail.com>
To: Questions@freebsd.org
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
X-Content-Filtered-By: Mailman/MimeDel 2.1.5
Cc: 
Subject: Developer's Handbook doubt
X-BeenThere: freebsd-questions@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: User questions <freebsd-questions.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-questions>
List-Post: <mailto:freebsd-questions@freebsd.org>
List-Help: <mailto:freebsd-questions-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-questions>, 
	<mailto:freebsd-questions-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 10 Dec 2008 16:51:12 -0000

Hi comunity.

I'm a developer new in the FreeBSD world and I'm reading the handbook. I
have a doubt regarding the following code example (page 103):

open:
push dword mode
push dword flags
push dword path
mov eax, 5
push eax ; Or any other dword
int 80h
add esp, byte 16

Why is required the "push eax;" sentence? (I guess a basic assembler concept
unknown to me)

Thank you very much

Regards

Pablo Caballero