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From: "Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>
Subject: Re: Alternative Index implementation? (Was: Reading and writing a big
 file in Ada (GNAT) on Windows XP)
Newsgroups: comp.lang.ada
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Date: Fri, 4 May 2007 09:41:58 +0200
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Date: 2007-05-04T09:41:57+02:00
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On Fri, 04 May 2007 08:53:59 +0200, Jacob Sparre Andersen wrote:

> My demonstration of how you can make a fast implementation of the Unix
> command "tail" with POSIX.Memory_Mapping was not very successful, and
> I suspect that the sinner may be Index.

[...]

>      for Lines in 1 .. 10 loop
>         Last := Index (Source  => Text (Text'First .. Last - 1),

Did you check if GNAT did not copy the string slice before calling to
Index?

>                        Pattern => (1 => Latin_1.LF),
>                        Going   => Backward);
>         exit when Last = 0;
>      end loop;

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de