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From: Mike Williams on 8 Jun 2010 04:54
"Jeff Johnson" <i.get(a)enough.spam> wrote in message
news:hujqu9$v41$1(a)news.eternal-september.org...
> "David Kaye" <sfdavidkaye2(a)yahoo.com> wrote in message
>> The CRLF format is peculiar to DOS and Windows.
>
> In the sense of they're the only surviving major OSes that use
> that convention. They certainly didn't invent it just to be
> different; they inherited it from their predecessors.

.. . . who themselves inherited it from the old fashioned manual typewriter,
although in the case of the manual typewriter it was LF followed by CR.

Mike




From: Helmut Meukel on 8 Jun 2010 07:34
"Mike Williams" <Mike(a)WhiskeyAndCoke.com> schrieb im Newsbeitrag
news:O$rSzguBLHA.980(a)TK2MSFTNGP04.phx.gbl...
> "Jeff Johnson" <i.get(a)enough.spam> wrote in message
> news:hujqu9$v41$1(a)news.eternal-september.org...
>> "David Kaye" <sfdavidkaye2(a)yahoo.com> wrote in message
>>> The CRLF format is peculiar to DOS and Windows.
>>
>> In the sense of they're the only surviving major OSes that use
>> that convention. They certainly didn't invent it just to be
>> different; they inherited it from their predecessors.
>
> . . . who themselves inherited it from the old fashioned manual typewriter,
> although in the case of the manual typewriter it was LF followed by CR.
>
> Mike
>


Mike,

I can't remember the sequence my old manual typewriter performed the tasks,
it probably differed from manufacturer to manufacturer, and I never used an
electrical typewriter. I however used/programmed a typewriter in the
mid-seventies and while you could first punch LF followed by CR it was
*not* advisable to do so. The first character on the new line wouldn't be in
the leftmost position due to the latency time of the mechanical equipment.
In other words, the next character was printed while the print head was still
moving to the left side.
They had deliberately shortened the delay after a CR to increase overall
print speed. If you used CR-LF this didn't matter, the line feed could
happen while the print head was still moving.

Helmut.

From: Mike Williams on 8 Jun 2010 08:22
"Helmut Meukel" <Helmut_Meukel(a)NoProvider.de> wrote in message
news:hul9re$4o7$1(a)news.eternal-september.org...

> Mike, I can't remember the sequence my old manual
> typewriter performed the tasks, it probably differed
> from manufacturer to manufacturer

As far as I recall it was the same for every manufacturer, and with good
reason. Both the line feed (the rotation of the roller around which the
paper was fed) and the carriage return (the actual sliding of the entire
carriage from left to right) were performed with just one lever. The user
moved the lever and the first part of the lever movement caused the
mechanism to first rotate the roller (line feed) and whilst it was doing
that it did not meet with sufficent mechanical resistance to actually begin
to move the carriage along. It was only after it has rotated the roller by
the equivalent of one line (using the first small amount of the user's lever
movement) that the lever came up against the mechanical roller stop, and the
rest of the user's continued movement of the lever then caused to carriage
to move along. This enabled the user to perform both a line feed and a
carriage return (an often required action) with one single movement of the
lever, and it also allowed the user to perform just a line feed without a
carriage return (another often required action) simply by moving the same
lever just a short amount, without continuing to move it once the "begin to
move the carriage" resistance was felt (for line spacing between paragraphs
etc and whenever else it was required to position the next line a number of
lines below the preceeding one).

> I however used/programmed a typewriter in the
> mid-seventies and while you could first punch LF
> followed by CR it was *not* advisable to do so.
> The first character on the new line wouldn't be in
> the leftmost position due to the latency time of the
> mechanical equipment.

Ah, but that's not what I would call a manual typewriter. It's one of those
new fangled beasts with the fancy electric motors! And of course it
certainly does not pre-date the manual typewriters that I am talking about
;-)

Mike




From: ralph on 8 Jun 2010 16:51
On Tue, 8 Jun 2010 09:54:26 +0100, "Mike Williams"
<Mike(a)WhiskeyAndCoke.com> wrote:

>"Jeff Johnson" <i.get(a)enough.spam> wrote in message
>news:hujqu9$v41$1(a)news.eternal-september.org...
>> "David Kaye" <sfdavidkaye2(a)yahoo.com> wrote in message
>>> The CRLF format is peculiar to DOS and Windows.
>>
>> In the sense of they're the only surviving major OSes that use
>> that convention. They certainly didn't invent it just to be
>> different; they inherited it from their predecessors.
>
>. . . who themselves inherited it from the old fashioned manual typewriter,
>although in the case of the manual typewriter it was LF followed by CR.
>

It will perhaps make more sense if you appreciate that 'Line Printing"
came from Telegraphy/Teletype devices, not 'manual typewriters'.

Various conventions came about to abstract the notion of a "New Line".
Many of these conventions overloaded a specific value in order to save
clicks/space. So whenever one takes a closer look they have to
consider the context under which a "NewLine" is defined or expected.

For example, the reason Lf/Cr may occasionally fail under a particular
scheme - is because it is not recognized as a "NewLine" while Cr/Lf is
- even though literal control defined by each in whatever order
produces the same result.
From: Chris Dunaway on 8 Jun 2010 17:18
On Jun 8, 7:22 am, "Mike Williams" <M...(a)WhiskeyAndCoke.com> wrote:
> "Helmut Meukel" <Helmut_Meu...(a)NoProvider.de> wrote in message
>
>
> > I however used/programmed a typewriter in the
> > mid-seventies and while you could first punch  LF
> > followed by CR it was *not* advisable to do so.
> > The first character on the new line wouldn't be in
> > the leftmost position due to the latency time of the
> > mechanical equipment.
>
> Ah, but that's not what I would call a manual typewriter. It's one of those
> new fangled beasts with the fancy electric motors! And of course it
> certainly does not pre-date the manual typewriters that I am talking about
> ;-)
>
> Mike

You're probably referring to a good old-fashioned Underwood
typewriter! I used to use one of those! Young kids these days and
their new-fangled electricity!

Chris
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