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Re: Deleting first N lines from a text file

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"BartC" <bc@freeuk.com> writes:

> "Ian Collins" <ian-news@hotmail.com> wrote in message
> news:9ijan5Fi5oU19@mid.individual.net...
>> On 11/17/11 03:32 PM, Eric Sosman wrote:
>>> On 11/16/2011 9:26 AM, BartC wrote:
>>>> "pozz"<pozzugno@gmail.com>  wrote in message
>>>> news:f06508a1-a424-4bc7-99f6-98e94e6944e6@w7g2000yqc.googlegroups.com...
>>>>> On 16 Nov, 03:48, Eric Sosman<esos...@ieee-dot-org.invalid>  wrote:
>>>>>> [...]
>>>>>> Fifty K shouldn't take long. Even on a system from forty years
>>>>>> ago it didn't take long. Even on paper tape, for goodness' sake, it
>>>>>> took less than a minute!
>>>>
>>>> (That's a fast paper tape reader. The last one I used would have taken
>>>> nearly 3 hours.)
>>>
>>>       http://www.springerlink.com/content/x42n45gk4811lpq1/ from 1963
>>> describes a "high speed paper tape reader with a maximum speed of
>>> 1000 characters per second."  50KB / (1000 B/s) = 50s<  one minute.
>>
>> That modern?  The machine that preceded Colossus at Bletchley Park
>> in the early 40s could read paper tape at 1000 characters per
>> second!
>
> I've seen Colossus itself in action (the replica, not the original!)
> and apparently it could read paper tape at 5000 characters per second.
>
> I think that might have been the program itself, on an endless loop.

That loop is the message that is being attacked.  The machine runs the
message through, does some operations on it and carries out a set of
counts on the results.  If the answer is "interesting" it outputs the
fact, otherwise it advances its internal state and repeats.  The
internal state is on uniselctors - electromechanically - and so you get
a "clunk" once per tape loop as it advances.  The counters are valve for
speed.
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Deleting first N lines from a text file pozz <pozzugno@gmail.com> - 2011-11-14 16:02 -0800
  Re: Deleting first N lines from a text file Roberto Waltman <usenet@rwaltman.com> - 2011-11-14 19:21 -0500
    Re: Deleting first N lines from a text file Acid Washed China Blue Jeans <chine.bleu@yahoo.com> - 2011-11-14 16:31 -0800
      Re: Deleting first N lines from a text file blp@cs.stanford.edu (Ben Pfaff) - 2011-11-14 16:36 -0800
      Re: Deleting first N lines from a text file Roberto Waltman <usenet@rwaltman.com> - 2011-11-14 20:10 -0500
      Re: Deleting first N lines from a text file Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-11-16 11:04 +0200
  Re: Deleting first N lines from a text file gordonb.3hlvm@burditt.org (Gordon Burditt) - 2011-11-14 18:53 -0600
  Re: Deleting first N lines from a text file Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-14 22:06 -0500
    Re: Deleting first N lines from a text file Giuseppe <giuseppe.modugno@gmail.com> - 2011-11-15 16:57 -0800
      Re: Deleting first N lines from a text file Keith Thompson <kst-u@mib.org> - 2011-11-15 17:50 -0800
        Re: Deleting first N lines from a text file pozz <pozzugno@gmail.com> - 2011-11-15 23:11 -0800
          Re: Deleting first N lines from a text file jgharston <jgh@arcade.demon.co.uk> - 2011-11-16 04:11 -0800
      Re: Deleting first N lines from a text file Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-15 21:48 -0500
        Re: Deleting first N lines from a text file pozz <pozzugno@gmail.com> - 2011-11-15 23:14 -0800
          Re: Deleting first N lines from a text file "BartC" <bc@freeuk.com> - 2011-11-16 14:26 +0000
            Re: Deleting first N lines from a text file Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-11-16 21:32 -0500
              Re: Deleting first N lines from a text file Ian Collins <ian-news@hotmail.com> - 2011-11-17 15:43 +1300
                Re: Deleting first N lines from a text file "BartC" <bc@freeuk.com> - 2011-11-17 10:35 +0000
                Re: Deleting first N lines from a text file Dr Nick <3-nospam@temporary-address.org.uk> - 2011-12-16 07:05 +0000
              Re: Deleting first N lines from a text file Robert Wessel <robertwessel2@yahoo.com> - 2011-11-16 22:46 -0600
      Re: Deleting first N lines from a text file gordonb.pa5u0@burditt.org (Gordon Burditt) - 2011-11-16 16:28 -0600
        Re: Deleting first N lines from a text file Kaz Kylheku <kaz@kylheku.com> - 2011-11-16 22:53 +0000
          Re: Deleting first N lines from a text file gordonb.z5i2o@burditt.org (Gordon Burditt) - 2011-11-16 18:34 -0600
  Re: Deleting first N lines from a text file jacob navia <jacob@spamsink.net> - 2011-11-15 12:48 +0100
    Re: Deleting first N lines from a text file "-.-" <none@none.none> - 2011-11-16 14:01 +0100
      Re: Deleting first N lines from a text file jacob navia <jacob@spamsink.net> - 2011-11-16 14:44 +0100
        Re: Deleting first N lines from a text file tom st denis <tom@iahu.ca> - 2011-11-17 10:43 -0800
          Re: Deleting first N lines from a text file jt@toerring.de (Jens Thoms Toerring) - 2011-11-18 23:12 +0000
  Re: Deleting first N lines from a text file jgharston <jgh@arcade.demon.co.uk> - 2011-11-16 06:42 -0800
    Re: Deleting first N lines from a text file jgharston <jgh@arcade.demon.co.uk> - 2011-11-16 07:43 -0800
    Re: Deleting first N lines from a text file Keith Thompson <kst-u@mib.org> - 2011-11-16 11:13 -0800
      Re: Deleting first N lines from a text file jgharston <jgh@arcade.demon.co.uk> - 2011-11-16 13:50 -0800

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