From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.5-pre1 (2020-06-20) on
	ip-172-31-74-118.ec2.internal
X-Spam-Level: 
X-Spam-Status: No, score=0.0 required=3.0 tests=BAYES_40,FREEMAIL_FROM
	autolearn=ham autolearn_force=no version=3.4.5-pre1
X-Received: by 2002:ac8:43ce:: with SMTP id w14mr3990488qtn.0.1596204100108;
        Fri, 31 Jul 2020 07:01:40 -0700 (PDT)
X-Received: by 2002:a37:4811:: with SMTP id v17mr4263900qka.166.1596204099840;
 Fri, 31 Jul 2020 07:01:39 -0700 (PDT)
Path: eternal-september.org!reader01.eternal-september.org!feeder.eternal-september.org!aioe.org!peer03.ams4!peer.am4.highwinds-media.com!peer02.iad!feed-me.highwinds-media.com!news.highwinds-media.com!news-out.google.com!nntp.google.com!postnews.google.com!google-groups.googlegroups.com!not-for-mail
Newsgroups: comp.lang.ada
Date: Fri, 31 Jul 2020 07:01:39 -0700 (PDT)
In-Reply-To: <00cd3aaa-d518-43a2-b321-58d6fae70aebo@googlegroups.com>
Complaints-To: groups-abuse@google.com
Injection-Info: google-groups.googlegroups.com; posting-host=146.5.2.231; posting-account=lJ3JNwoAAAAQfH3VV9vttJLkThaxtTfC
NNTP-Posting-Host: 146.5.2.231
References: <e3c51e65-b71e-4623-bd58-c94cdbcc3ba6o@googlegroups.com> <00cd3aaa-d518-43a2-b321-58d6fae70aebo@googlegroups.com>
User-Agent: G2/1.0
MIME-Version: 1.0
Message-ID: <476a352b-6f81-433d-9638-e941a2631be4o@googlegroups.com>
Subject: Re: is there a version of unix written in Ada
From: Shark8 <onewingedshark@gmail.com>
Injection-Date: Fri, 31 Jul 2020 14:01:40 +0000
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Received-Bytes: 3174
X-Received-Body-CRC: 1526422071
Xref: reader01.eternal-september.org comp.lang.ada:59612
List-Id: <comp.lang.ada>

On Wednesday, July 29, 2020 at 6:57:07 PM UTC-6, gdo...@gmail.com wrote:
> On Friday, July 24, 2020 at 6:11:49 PM UTC-4, gdo...@gmail.com wrote:
> > is there a unix like OS written completely in Ada?
>=20
> i don't quite remember where i read C was not intended=20
> for coding in the million of line, but it has done
> some amazing work for something not intended. It=20
> seems that Ada was intended to handle such massively=20
> large coding efforts. i guess though an OS unix in=20
> type maybe done with a 100,000 lines or so. i have wondered
> with the language features would using produce a secure
> os, with much less need for security updates.
>=20
> Thanks everyone, it is more than clear Ada can do an OS, from the=20
> realtime OS links.

Part of the issue with security is also on the underlying methodology/desig=
n of the system. One good example here is the "text-first" approach of the =
command-line, especially if you're piping together inputs and outputs: inhe=
rent to this is the forced ad hoc re-parsing of of data. This text-first ap=
proach is quick because it's easier, at first, but more error-prone; see he=
re: https://www.reddit.com/r/programming/comments/faxlva/i_want_off_mr_gola=
ngs_wild_ride/fj2z4zi?utm_source=3Dshare&utm_medium=3Dweb2x

To contrast, here's an alternative & proper design for command-line:
(1) Have an underlying typesystem the operating-system is aware of.
(2) Have objects in this typesystem with round-trip stable serialize/desera=
lize functions.
(3) Have the command-line interpreter parse the commands into streams of th=
ese objects. [This should be done by a common OS-library.]
(4) Have programs with streams for input and output.

And now you have a system which not only has a consistent interface, but re=
quires less cycles (due to not having to re-parse data), and is more secure=
.