From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-1.9 required=5.0 tests=BAYES_00 autolearn=ham
	autolearn_force=no version=3.4.4
X-Google-Language: ENGLISH,ASCII-7-bit
X-Google-Thread: 103376,216b18d81cce4f75
X-Google-Attributes: gid103376,public
X-Google-ArrivalTime: 2001-06-02 18:09:23 PST
Path: 
 archiver1.google.com!newsfeed.google.com!newsfeed.stanford.edu!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!news.stealth.net!204.127.161.2.MISMATCH!wn2feed!worldnet.att.net!135.173.83.71!wnfilter1!worldnet-localpost!bgtnsc05-news.ops.worldnet.att.net.POSTED!not-for-mail
Message-ID: <3B198ED7.6FA8F8F7@worldnet.att.net>
From: James Rogers <jimmaureenrogers@worldnet.att.net>
X-Mailer: Mozilla 4.76 [en] (Win98; U)
X-Accept-Language: en
MIME-Version: 1.0
Newsgroups: comp.lang.ada
Subject: Re: Ada Microkernel?
References: <3B183CB8.3EE396E7@engineer.com>
 <_M3S6.8957$HL5.1284411@news6-win.server.ntlworld.com>
 <t1cS6.16384$DG1.3250771@news1.rdc1.mi.home.com>
 <3B1958AD.F7D7A5CC@engineer.com> <3B195D98.C220C407@engineer.com>
Content-Type: text/plain; charset=us-ascii
Content-Transfer-Encoding: 7bit
Date: Sun, 03 Jun 2001 01:09:22 GMT
NNTP-Posting-Host: 12.82.160.237
X-Complaints-To: abuse@worldnet.att.net
X-Trace: bgtnsc05-news.ops.worldnet.att.net 991530562 12.82.160.237 (Sun,
 03 Jun 2001 01:09:22 GMT)
NNTP-Posting-Date: Sun, 03 Jun 2001 01:09:22 GMT
Organization: AT&T Worldnet
Xref: archiver1.google.com comp.lang.ada:8030
Date: 2001-06-03T01:09:22+00:00
List-Id: <comp.lang.ada>

"B. Douglas Hilton" wrote:
> 
> Ok, here is the oskit "hello" kernel. Any ideas how to convert this
> to Ada?
> 
> #include <stdio.h>
> #include <oskit/clientos.h>
> #include <oskit/startup.h>
> #include <oskit/version.h>
> 
> int main()
> {
> #ifndef KNIT
>         oskit_clientos_init();
> #endif
> #ifdef  GPROF
>         start_fs_bmod();
>         start_gprof();
> #endif
>         oskit_print_version();
>         printf("Hello, World\n");
>         return 0;
> }
> 

The first rule to learn is that Ada should be written as Ada and
C should be written as C. 

Clearly, any standard Ada version would not use a preprocessor.

The C preprocessor conditionals provide for conditional compilation
of the C sources. The Ada way to achieve the same goal is to
provide several versions of the entry point procedure for the 
program, each one specifying its own set of dependencies.

Each of the include files in the C version will require a
corresponding Ada package. The Ada package corresponding to stdio.h
is clearly Ada.Text_Io. Each of the other included files must
be rewritten in Ada.

One version of the Ada entry point procedure might look like the
following:

with Oskit.ClientOs;
with OsKit.Startup;
with OsKit.Version;
with Ada.Text_Io;

procedure HelloKernel is
begin
   OsKit.ClientOs.Init;
   OsKit.Startup.FsBmod;
   OsKit.Startup.Gprof;
   OsKit.Version.Print;
   Ada.Text_Io.Put_Line("Hello World!");
end HelloKernel;

Jim Rogers
Colorado Springs, Colorado USA