Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sources.redhat.com/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sources.redhat.com/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com
content-class: urn:content-classes:message
MIME-Version: 1.0
Content-Type: text/plain; charset="Windows-1252"
Subject: RE: Assembler
Date: Tue, 17 Feb 2004 15:12:05 -0500
Message-ID: <AE2AA130827456459AA497E8C9D6EA00412C02@pauex2ku02.agere.com>
X-MS-Has-Attach: 
X-MS-TNEF-Correlator: 
From: "Williams, Gerald S (Jerry)" <gsw AT agere DOT com>
To: <cygwin AT cygwin DOT com>
X-OriginalArrivalTime: 17 Feb 2004 20:12:05.0263 (UTC) FILETIME=[4FFEB9F0:01C3F592]
Content-Transfer-Encoding: 8bit
X-MIME-Autoconverted: from quoted-printable to 8bit by delorie.com id i1HKCJ4q011569

Krzysztof Duleba wrote:
> What about Linux syscalls? Will Cygwin emulation layer match 
> it?

I just Googled "int 0x80". So THAT'S what you're
trying to do. :-)

No, I think your experiment shows that Cygwin is
not emulating Linux syscalls at that level. Nor
would I have expected it to.

On the other hand, you can get at DOS functions,
at least if you build your executable correctly.
For example, the following:

 ; hello.asm
 [ORG 0x100]
 
 section .text
 global  _start
 
 _start: mov     ah,9
         mov     dx, hello
         int     0x21
 
         mov     ax,0x4c00
         int     0x21
 
 section .data
 hello   db      'Hello, World', 13, 10, '$'

can be converted into a .COM file and run via:

 nasm -o hello.com hello.asm
 chmod +x hello.com # to avoid "Permission denied"
 ./hello.com

> Is there a way I could force Cygwin's ld to work the way 
> Linux ld used to?

I don't know about that, but you can specify the
entry point explicitly:

  ld -e _start hello.o

-Jerry

--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/