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=-1.8 required=5.0 tests=BAYES_00,TRACKER_ID
	autolearn=no autolearn_force=no version=3.4.4
Path: 
 eternal-september.org!reader01.eternal-september.org!reader02.eternal-september.org!news.eternal-september.org!mx02.eternal-september.org!.POSTED!not-for-mail
From: "Jeffrey R. Carter" <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Problem with Unbounded Strings
Date: Fri, 4 Dec 2015 15:28:42 -0700
Organization: Also freenews.netfront.net; news.tornevall.net;
 news.eternal-september.org
Message-ID: <n3t3u8$fmk$1@dont-email.me>
References: <e28c35a7-5f41-4beb-afb3-eb4fc9da9384@googlegroups.com>
 <n3sklk$fpv$1@dont-email.me>
 <274dc49b-b7cd-4eef-b333-34bae665c992@googlegroups.com>
Mime-Version: 1.0
Content-Type: text/plain; charset=windows-1252
Content-Transfer-Encoding: 7bit
Injection-Date: Fri, 4 Dec 2015 22:26:18 -0000 (UTC)
Injection-Info: mx02.eternal-september.org;
 posting-host="caa759af2a9c666aec02942f6fe5abd6";
	logging-data="16084"; mail-complaints-to="abuse@eternal-september.org";
	posting-account="U2FsdGVkX189UmVfSKaLepUYd34goM+FJlRhMqYpXgw="
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101
 Thunderbird/38.3.0
In-Reply-To: <274dc49b-b7cd-4eef-b333-34bae665c992@googlegroups.com>
Cancel-Lock: sha1:8RSiXi5ll2c7lTJyUvnxyj1dmO8=
X-Enigmail-Draft-Status: N1110
Xref: news.eternal-september.org comp.lang.ada:28648
Date: 2015-12-04T15:28:42-07:00
List-Id: <comp.lang.ada>

On 12/04/2015 02:21 PM, Laurent wrote:
> 
> 1st read: 0123456789
> append to the buffer which is empty so content of buffer is: 0123456789
> 
> 2nd read: abcdefghijklmnopqrstuvwxyz
> append to buffer so it becomes: 0123456789abcdefghijklmnopqrstuvwxyz
> 
> 3rd read: ABCDEFGHIJKLMNOPQRSTUVWXYZ
> append to buffer so it would be: 0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ

This is what your code does for me, compiled with GNAT 4.9.2 under Linux Mint
Debian Edition.

One possible explanation is that your file was produced by a Windows system, and
you're running your program on a Unix-based platform. In that case, Get_Line
will return a string with a CR at the end. When displayed, the CR will return
the cursor to the beginning of the line. So you begin by outputting

Buffer after append: 0123456789

You then output the CR, and the cursor returns to the beginning of the line.
Then you output

abcdefghijklmnopqrstuvwxyz

which overwrites everything already displayed through the '4'.

-- 
Jeff Carter
"Well, a gala day is enough for me. I don't think
I can handle any more."
Duck Soup
93