By using this site, you agree to our updated Privacy Policy and our Terms of Use. Manage your Cookies Settings.
424,688 Members | 1,845 Online
Bytes IT Community
+ Ask a Question
Need help? Post your question and get tips & solutions from a community of 424,688 IT Pros & Developers. It's quick & easy.

normalization of pointers...

P: n/a
What is mean by normalization of pointers...Where we use that?

May 30 '07 #1
Share this Question
Share on Google+
36 Replies


P: n/a
Shraddha wrote:
What is mean by normalization of pointers...Where we use that?
We don't. There's no such concept in Standard C.

Tell us more about your problem.

--
"A facility for quotation covers the absence of original thought."/Gaudy Night/

Hewlett-Packard Limited registered no:
registered office: Cain Road, Bracknell, Berks RG12 1HN 690597 England

May 30 '07 #2

P: n/a
On May 30, 6:29 pm, Chris Dollin <chris.dol...@hp.comwrote:
Shraddha wrote:
What is mean by normalization of pointers...Where we use that?

We don't. There's no such concept in Standard C.

Tell us more about your problem.

--
"A facility for quotation covers the absence of original thought."/Gaudy Night/

Hewlett-Packard Limited registered no:
registered office: Cain Road, Bracknell, Berks RG12 1HN 690597 England

May 30 '07 #3

P: n/a
On May 30, 6:29 pm, Chris Dollin <chris.dol...@hp.comwrote:
Shraddha wrote:
What is mean by normalization of pointers...Where we use that?

We don't. There's no such concept in Standard C.

Tell us more about your problem.

--
"A facility for quotation covers the absence of original thought."/Gaudy Night/

Hewlett-Packard Limited registered no:
registered office: Cain Road, Bracknell, Berks RG12 1HN 690597 England
I read about it in the explanation of the far pointers...
there they say that -"The only difference between huge pointers and
far pointers is that...huge pointers are normalized..."

So I am asking what is far pointers?

May 30 '07 #4

P: n/a
On May 30, 9:43 am, Shraddha <shraddhajosh...@gmail.comwrote:
[snip]
So I am asking what is far pointers?
"far" pointers do not exist in C

They exist in some C-like languages (primarily, those designed by
Microsoft) as a way of expressing a pointer on an Intel processor
platform. You probably want to ask your question in either an Intel or
a Microsoft group.

May 30 '07 #5

P: n/a
On 5月30日, 下午9时43分, Shraddha <shraddhajosh...@gmail.comwrote:
On May 30, 6:29 pm, Chris Dollin <chris.dol...@hp.comwrote:
Shraddha wrote:
What is mean by normalization of pointers...Where we use that?
We don't. There's no such concept in Standard C.
Tell us more about your problem.
--
"A facility for quotation covers the absence of original thought."/Gaudy Night/
Hewlett-Packard Limited registered no:
registered office: Cain Road, Bracknell, Berks RG12 1HN 690597England

I read about it in the explanation of the far pointers...
there they say that -"The only difference between huge pointers and
far pointers is that...huge pointers are normalized..."

So I am asking what is far pointers?
The huge pointer and far pointer are old concept which live in 16-bit
DOS time. You can search something about DOS programming for more
detail about them.

May 30 '07 #6

P: n/a
Shraddha wrote:
On May 30, 6:29 pm, Chris Dollin <chris.dol...@hp.comwrote:
>Shraddha wrote:
What is mean by normalization of pointers...Where we use that?

We don't. There's no such concept in Standard C.

Tell us more about your problem.
(and remember to snip signatures in the future)
I read about it in the explanation of the far pointers...
there they say that -"The only difference between huge pointers and
far pointers is that...huge pointers are normalized..."

So I am asking what is far pointers?
They are not a feature of Standard C; they are a non-standard
(and, as I understand it, largely obsolete) feature of certain
implementations.

I'd advise learning C from a source that isn't so implementation-
specific. (My preference is for K&R 2; others differ.)

--
"Who are you? What do you want?" /Babylon 5/

Hewlett-Packard Limited registered no:
registered office: Cain Road, Bracknell, Berks RG12 1HN 690597 England

May 30 '07 #7

P: n/a
In article <f3**********@murdoch.hpl.hp.com>, Chris Dollin
<ch**********@hp.comwrites
>Shraddha wrote:
>On May 30, 6:29 pm, Chris Dollin <chris.dol...@hp.comwrote:
>>Shraddha wrote:
What is mean by normalization of pointers...Where we use that?

We don't. There's no such concept in Standard C.

Tell us more about your problem.

(and remember to snip signatures in the future)
>I read about it in the explanation of the far pointers...
there they say that -"The only difference between huge pointers and
far pointers is that...huge pointers are normalized..."

So I am asking what is far pointers?

They are not a feature of Standard C; they are a non-standard
(and, as I understand it, largely obsolete) feature of certain
implementations.

I'd advise learning C from a source that isn't so implementation-
specific. (My preference is for K&R 2; others differ.)
Many compilers have FAR pointers. Not just WinTel stuff. Not just in old
compilers either.
--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

May 30 '07 #8

P: n/a
In article <11*********************@q69g2000hsb.googlegroups. com>, Lew
Pitcher <lp******@teksavvy.comwrites
>On May 30, 9:43 am, Shraddha <shraddhajosh...@gmail.comwrote:
[snip]
>So I am asking what is far pointers?

"far" pointers do not exist in C

They exist in some C-like languages (primarily, those designed by
Microsoft)
This is not correct. I have lots of compilers, NONE by Microsoft or for
x86 targets that have FAR pointers.
>as a way of expressing a pointer on an Intel processor
Or many others.

--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

May 30 '07 #9

P: n/a
Shraddha wrote:
Chris Dollin <chris.dol...@hp.comwrote:
>Shraddha wrote:
>>What is mean by normalization of pointers...Where we use that?

We don't. There's no such concept in Standard C.

Tell us more about your problem.
.... snip sig ...
>
I read about it in the explanation of the far pointers...
there they say that -"The only difference between huge pointers
and far pointers is that...huge pointers are normalized..."

So I am asking what is far pointers?
They are obsolete, used on the obsolete 8086 (not 80x86)
architecture, to provide access to a 1 megabyte address space with
16 bit registers. Ignore the word 'far'.

--
<http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt>
<http://www.securityfocus.com/columnists/423>
<http://www.aaxnet.com/editor/edit043.html>
<http://kadaitcha.cx/vista/dogsbreakfast/index.html>
cbfalconer at maineline dot net

--
Posted via a free Usenet account from http://www.teranews.com

May 30 '07 #10

P: n/a
Shraddha wrote:
>
What is mean by normalization of pointers...Where we use that?
We don't.

--
<http://www.cs.auckland.ac.nz/~pgut001/pubs/vista_cost.txt>
<http://www.securityfocus.com/columnists/423>
<http://www.aaxnet.com/editor/edit043.html>
<http://kadaitcha.cx/vista/dogsbreakfast/index.html>
cbfalconer at maineline dot net

--
Posted via a free Usenet account from http://www.teranews.com

May 30 '07 #11

P: n/a
Chris Hills wrote:
In article <f3**********@murdoch.hpl.hp.com>, Chris Dollin
<ch**********@hp.comwrites
>>Shraddha wrote:
>>So I am asking what is far pointers?

They are not a feature of Standard C; they are a non-standard
(and, as I understand it, largely obsolete) feature of certain
implementations.

I'd advise learning C from a source that isn't so implementation-
specific. (My preference is for K&R 2; others differ.)

Many compilers have FAR pointers.
Perhaps many do. None of those FAR (or `far` or `_far`) pointers
are Standard C, though, which is my main point above.
Not just WinTel stuff.
I didn't say Windows. Even if I thought it. Did I?
Not just in old compilers either.
I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".

--
"I'm still here and I'm holding the answers" - Karnataka, /Love and Affection/

Hewlett-Packard Limited Cain Road, Bracknell, registered no:
registered office: Berks RG12 1HN 690597 England

May 30 '07 #12

P: n/a
On May 30, 10:24 am, Chris Hills <c...@phaedsys.orgwrote:
So I am asking what is far pointers?
They are not a feature of Standard C; they are a non-standard
(and, as I understand it, largely obsolete) feature of certain
implementations.
I'd advise learning C from a source that isn't so implementation-
specific. (My preference is for K&R 2; others differ.)

Many compilers have FAR pointers. Not just WinTel stuff. Not just in old
compilers either.
I suppose they target some architectures where the memory model is not
the tiny model. Am I right?

May 30 '07 #13

P: n/a
In article <11*********************@o5g2000hsb.googlegroups.c om>,
Quentin Godfroy <qu*************@hotmail.comwrites
>On May 30, 10:24 am, Chris Hills <c...@phaedsys.orgwrote:
>So I am asking what is far pointers?
>They are not a feature of Standard C; they are a non-standard
(and, as I understand it, largely obsolete) feature of certain
implementations.
>I'd advise learning C from a source that isn't so implementation-
specific. (My preference is for K&R 2; others differ.)

Many compilers have FAR pointers. Not just WinTel stuff. Not just in old
compilers either.

I suppose they target some architectures where the memory model is not
the tiny model. Am I right?
Tiny? The first one I just picked up has small, compact and large. This
depends on if you have external memory or not. Some versions of the
target hardware, but not all by a long way, have a physical FAR memory
space hence the pointers. The also have a physical memory that is bit
addressable.

I think that you can actually use the FAR memory with pointers in all
three memory models by explicit declaration. I will have to look that
up tomorrow.
--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

May 30 '07 #14

P: n/a
Shraddha wrote:
>
On May 30, 6:29 pm, Chris Dollin <chris.dol...@hp.comwrote:
Shraddha wrote:
What is mean by normalization of pointers...Where we use that?
We don't. There's no such concept in Standard C.

Tell us more about your problem.

I read about it in the explanation of the far pointers...
there they say that -"The only difference between huge pointers and
far pointers is that...huge pointers are normalized..."
Note that "near", "far", "normalized", and so on are not part of
the C standard.

However, in the context of that original discussion...

Some hardware uses a "segmented" memory architecture. For example,
the x86 series of processors have a "real mode" mode, in which you
access memory via a pointer consisting of a 16-bit segment and a
16-bit offset, in which the physical address is obtained by taking
(segment*16 + offset). In such a model, multiple segment/offset
combinations can point to the same physical memory locaation. For
example F000:FFF0 and FFFF:0000 both point to FFFF0.

In such a model, you can "normalize" the pointer by making sure
that the offset is always less than 0x10. In other words, if the
physical address ix 0xABCDE, then you normalize it to ABCD:000E.
This guarantees that there is but a single normalized pointer to
any given physical address, and you can compare any normalized
pointers as simple 32-bit values.
So I am asking what is far pointers?
"Far" pointers consist of both the segment and offset. A "near"
pointer would consis of just the offset, with the segment value
gotten elsewhere. (For example, on the x86, it could be either
the DS or SS segment register.)

--
+-------------------------+--------------------+-----------------------+
| Kenneth J. Brody | www.hvcomputer.com | #include |
| kenbrody/at\spamcop.net | www.fptech.com | <std_disclaimer.h|
+-------------------------+--------------------+-----------------------+
Don't e-mail me at: <mailto:Th*************@gmail.com>

May 30 '07 #15

P: n/a
"Chris Dollin" <ch**********@hp.comwrote in message
I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".
Most people program PCs most of the time, and segmented architecture was
dumped years ago. However most chips are not CPUs in computer systems, and a
lot of them come with C compilers, and are fairly low power - you might have
4K of memory of which 256 bytes is RAM, for instance. Obviously you want to
squeeze RAM pointers into 8 bits.
--
Free games and programming goodies.
http://www.personal.leeds.ac.uk/~bgy1mm

May 30 '07 #16

P: n/a
On Wed, 30 May 2007 21:31:11 +0100, in comp.lang.c , "Malcolm McLean"
<re*******@btinternet.comwrote:
>"Chris Dollin" <ch**********@hp.comwrote in message
>I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".
Most people program PCs most of the time,
I beg to differ. Most people I know programme functionality not
hardware.
And I betcha the number of salaried embedded programmers still
outweighs wintelers.

--
Mark McIntyre

"Debugging is twice as hard as writing the code in the first place.
Therefore, if you write the code as cleverly as possible, you are,
by definition, not smart enough to debug it."
--Brian Kernighan
May 30 '07 #17

P: n/a
In article <ff********************************@4ax.com>,
Mark McIntyre <ma**********@spamcop.netwrote:
>On Wed, 30 May 2007 21:31:11 +0100, in comp.lang.c , "Malcolm McLean"
<re*******@btinternet.comwrote:
>>Most people program PCs most of the time,
Datum: I do servers, workstations, appliances, and occasionally my
Palm Pilot[1]. You could make a case for calling the workstation a PC,
but not any of the others, and workstations take up less than half of
my time-spent-programming and, in any given month, probably less than
at least one of the others. Not exactly "most of the time".

>I beg to differ. Most people I know programme functionality not
hardware.
The functionality I do is recognizeably, though perhaps not tightly,
bound to the type of hardware (at least at the general-class-of level,
though usually not at the architecture level) it will be running on.

>And I betcha the number of salaried embedded programmers still
outweighs wintelers.
Datum: At my day job, we ship a system running on Wintel that interfaces
with the outside world as a network-connected appliance (i.e. much the
same way some embedded systems would, and not at all like a PC would),
and everybody involved (including our manager) dreams of eventually moving
it to something that looks and feels more like an embedded system inside
the box as well. (We'd still need enough memory and CPU cycles that the
*real* embedded programmers would laugh and say "You call that embedded?",
but definitely not something any sensible person would call a PC.)
dave

[1] And I've written some code that could, and probably eventually
will, run on all of them, with no changes except which compiler I
feed it to.

--
Dave Vandervies dj******@csclub.uwaterloo.ca
I presume the difference is that Laurier's off-campus environment includes the
University of Waterloo, whereas the best we can offer by way of off-campus
environment is, well, Laurier. . . . --Chris Redmond in uw.general
May 31 '07 #18

P: n/a

"Mark McIntyre" <ma**********@spamcop.netwrote in message
news:ff********************************@4ax.com...
On Wed, 30 May 2007 21:31:11 +0100, in comp.lang.c , "Malcolm McLean"
<re*******@btinternet.comwrote:
>>"Chris Dollin" <ch**********@hp.comwrote in message
>>I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".
Most people program PCs most of the time,

I beg to differ. Most people I know programme functionality not
hardware.
In most PC programs most of the time is spent on the user interface. You are
writing to an API, but one very closely tied to the hardware.
That's maybe getting less true than it was. Processors are now fast enough
so you don't need to worry about updating the display efficiently. And there
are more hig-level tools about that arguably make it easier to tack up a UI.
>
And I betcha the number of salaried embedded programmers still
outweighs wintelers.
I don't know. When I did embedded stuff I still spent a great deal of time
writing supporting programs on PCs, though the final product was not a PC
program.
--
Free games and programming goodies.
http://www.personal.leeds.ac.uk/~bgy1mm

May 31 '07 #19

P: n/a
Malcolm McLean wrote:
"Chris Dollin" <ch**********@hp.comwrote in message
>I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".
Most people program PCs most of the time, and segmented architecture was
dumped years ago. However most chips are not CPUs in computer systems, and a
lot of them come with C compilers, and are fairly low power - you might have
4K of memory of which 256 bytes is RAM, for instance. Obviously you want to
squeeze RAM pointers into 8 bits.
I am more enlightened than I was; my workstation/PC bias was showing.

--
Yes, Virginia, there is a second Jena user conference: Palo Alto, Sep 2007.

Hewlett-Packard Limited registered no:
registered office: Cain Road, Bracknell, Berks RG12 1HN 690597 England

May 31 '07 #20

P: n/a
In article <ff********************************@4ax.com>, Mark McIntyre
<ma**********@spamcop.netwrites
>On Wed, 30 May 2007 21:31:11 +0100, in comp.lang.c , "Malcolm McLean"
<re*******@btinternet.comwrote:
>>"Chris Dollin" <ch**********@hp.comwrote in message
>>I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".
Most people program PCs most of the time,

I beg to differ. Most people I know programme functionality not
hardware.
And I betcha the number of salaried embedded programmers still
outweighs wintelers.
I would agree. The thing is most embedded SW people tend to also have a
background in hardware and don't hang around in SW groups because of the
PC bias.

--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

May 31 '07 #21

P: n/a
In article <j-*********************@bt.com>, Malcolm McLean
<re*******@btinternet.comwrites
>"Chris Dollin" <ch**********@hp.comwrote in message
>I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".
Most people program PCs most of the time,
That is not correct. However it is a common fallacy put around by those
whose programming stated and ended with PC's
and segmented architecture was dumped years ago. However most chips
are not CPUs in computer systems, and a lot of them come with C
compilers, and are fairly low power -
This is also completely incorrect. Low power as in low power
consumption, yes but I think it is only in the last 2 years that the
average main processor in a PC is more powerful than embedded MCU.
There have been embedded 64 and 128 bit MCU long before the PC started
using 64bit processors.
>you might have 4K of memory
Some 8 bit processors go up to 18Mega. byte
>of which 256 bytes is RAM, for instance. Obviously you want to squeeze
RAM pointers into 8 bits.
Yes.

--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

May 31 '07 #22

P: n/a
Malcolm McLean wrote:
>
"Mark McIntyre" <ma**********@spamcop.netwrote in message
news:ff********************************@4ax.com...
>On Wed, 30 May 2007 21:31:11 +0100, in comp.lang.c , "Malcolm McLean"
<re*******@btinternet.comwrote:
>>"Chris Dollin" <ch**********@hp.comwrote in message
I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".

Most people program PCs most of the time,

I beg to differ. Most people I know programme functionality not
hardware.
In most PC programs most of the time is spent on the user interface. You
are writing to an API, but one very closely tied to the hardware.
That's simply nonsense. The modern PC UI API is about as far away form
the hardware as you can get. Most (with one obvious exception) are
designed to be platform agnostic.

--
Ian Collins.
May 31 '07 #23

P: n/a
In article <f3**********@murdoch.hpl.hp.com>, Chris Dollin
<ch**********@hp.comwrites
>Malcolm McLean wrote:
>"Chris Dollin" <ch**********@hp.comwrote in message
>>I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".
Most people program PCs most of the time, and segmented architecture was
dumped years ago. However most chips are not CPUs in computer systems, and a
lot of them come with C compilers, and are fairly low power - you might have
4K of memory of which 256 bytes is RAM, for instance. Obviously you want to
squeeze RAM pointers into 8 bits.

I am more enlightened than I was; my workstation/PC bias was showing.
Just to give you some idea the last survey I saw, it is a paid for trade
one so I cant publish it here, puts the MCU use in PC's at about 5% of
the total MCU's shipped.

There are something like 100 MCU in the average car these days. Most
PC's have probably a 10 other MCU in them besides the main one.

The most common MCU on the planet (it think it is 30% by volume) is the
8 bit 8031.

Of course doing it by value changes the numbers quite a bit.

--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

May 31 '07 #24

P: n/a

"Chris Hills" <ch***@phaedsys.orgwrote in message
news:UQ**************@phaedsys.demon.co.uk...
In article <j-*********************@bt.com>, Malcolm McLean
<re*******@btinternet.comwrites
>>"Chris Dollin" <ch**********@hp.comwrote in message
>>I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".
Most people program PCs most of the time,

That is not correct. However it is a common fallacy put around by those
whose programming stated and ended with PC's
Aha. You are not such a limited person. So not subject to the fallacy.

But isn't your pride in that status based on the fact that most people write
programs for PCs?
--
Free games and programming goodies.
http://www.personal.leeds.ac.uk/~bgy1mm

May 31 '07 #25

P: n/a
On Thu, 31 May 2007 07:46:28 +0100, in comp.lang.c , "Malcolm McLean"
<re*******@btinternet.comwrote:
>In most PC programs most of the time is spent on the user interface. You are
writing to an API, but one very closely tied to the hardware.
You may want to rephrase that as "in most PC programs I have worked
with", to cater for those like myself whose experience has been
diametrically opposite.

I've worked on lots of apps that ran on PCs, but mostly they were a
thin layer of platform-specific UI over the top of a huge wodge of
analytical and computational code which was designed to be independent
of hardware. I forget when I last had the luxury of programming solely
for less than three platforms, though the mix has changed from
NT/SunOS/VMS to XP/Solaris/RHEL. Unless you count VBA....
--
Mark McIntyre

"Debugging is twice as hard as writing the code in the first place.
Therefore, if you write the code as cleverly as possible, you are,
by definition, not smart enough to debug it."
--Brian Kernighan
May 31 '07 #26

P: n/a

"Mark McIntyre" <ma**********@spamcop.netwrote in message
news:m0********************************@4ax.com...
On Thu, 31 May 2007 07:46:28 +0100, in comp.lang.c , "Malcolm McLean"
<re*******@btinternet.comwrote:
>>In most PC programs most of the time is spent on the user interface. You
are
writing to an API, but one very closely tied to the hardware.

You may want to rephrase that as "in most PC programs I have worked
with", to cater for those like myself whose experience has been
diametrically opposite.

I've worked on lots of apps that ran on PCs, but mostly they were a
thin layer of platform-specific UI over the top of a huge wodge of
analytical and computational code which was designed to be independent
of hardware. I forget when I last had the luxury of programming solely
for less than three platforms, though the mix has changed from
NT/SunOS/VMS to XP/Solaris/RHEL. Unless you count VBA....
A few years ago the general rule was that the amount of time needed to write
a program was determined by the complexity of its user interface.

Things have changed a bit now. Computers can carry out far more intensive
computations, and user-interface development technology has improved.
However I think there is still some truth in it.
--
Free games and programming goodies.
http://www.personal.leeds.ac.uk/~bgy1mm

May 31 '07 #27

P: n/a
Malcolm McLean wrote, On 31/05/07 22:45:
>
"Mark McIntyre" <ma**********@spamcop.netwrote in message
news:m0********************************@4ax.com...
>On Thu, 31 May 2007 07:46:28 +0100, in comp.lang.c , "Malcolm McLean"
<re*******@btinternet.comwrote:
>>In most PC programs most of the time is spent on the user interface.
You are
writing to an API, but one very closely tied to the hardware.

You may want to rephrase that as "in most PC programs I have worked
with", to cater for those like myself whose experience has been
diametrically opposite.

I've worked on lots of apps that ran on PCs, but mostly they were a
thin layer of platform-specific UI over the top of a huge wodge of
analytical and computational code which was designed to be independent
of hardware. I forget when I last had the luxury of programming solely
for less than three platforms, though the mix has changed from
NT/SunOS/VMS to XP/Solaris/RHEL. Unless you count VBA....
A few years ago the general rule was that the amount of time needed to
write a program was determined by the complexity of its user interface.

Things have changed a bit now. Computers can carry out far more
intensive computations, and user-interface development technology has
improved.
However I think there is still some truth in it.
It always has depended very much on the type of SW you are doing. I used
to do SW which was controlling test equipment and vastly more time was
spent writing code to control the equipment and analyse the results than
on doing the display, this back in the days before having a GUI was
common when we still has to display graphs. More recent simpler stuff
(running on W2K) I spent all of a couple of hours doing the display and
the rest of a week or two on the remainder of the SW.

The stuff I've spent the last few years doing, a small new routine might
be dominated by the time doing the screen layout, but on most stuff more
than a day the dominating factor is the business logic and database
work. So two tasks one taking a day and one taking a few weeks can have
close to the same amount of complexity on the user interface.

On other types of SW what you say may well be true. It's just not true
on the types of SW I've worked on or that Mark has worked on.
--
Flash Gordon
Jun 1 '07 #28

P: n/a
In article <yM******************************@bt.com>, Malcolm McLean
<re*******@btinternet.comwrites
>
"Chris Hills" <ch***@phaedsys.orgwrote in message
news:UQ**************@phaedsys.demon.co.uk...
>In article <j-*********************@bt.com>, Malcolm McLean
<re*******@btinternet.comwrites
>>>"Chris Dollin" <ch**********@hp.comwrote in message
I didn't say "old compilers", either. I understood this /feature/
to be largely /obsolete/; perhaps I'm wrong. Perhaps it depends
on the scope of the "largely".

Most people program PCs most of the time,

That is not correct. However it is a common fallacy put around by
those whose programming stated and ended with PC's
Aha. You are not such a limited person. So not subject to the fallacy.

But isn't your pride in that status based on the fact that most people
write programs for PCs?
I don't think most people do write programs for PC's , probably not
since the games console was invented and a large chunk of PC programming
moved to consoles. You only hjave to look around you to see the man y
things that have an MCU in (cars have 100+ these days and usually 2 or 3
separate networks. We are talking 8-64 but MCU.

There isn't a household appliance that does not have an MCU in it from
toasters to vacuum cleaners. For every PC there are thousands of
embedded systems. There are many systems that still run on mainframes.
(Or non windows/Linux compilers that may be x86 based)

The worlds telephone system (and every modern telephone on it) is a
large embedded system and they don't use PC's.

In fact numerous as PC's are they there are far more embedded systems.
These are not al 8 bit systems but 4-128 bits...... I was programming 64
bit embedded systems well over a decade ago.





--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

Jun 1 '07 #29

P: n/a
On May 30, 6:43 pm, Shraddha <shraddhajosh...@gmail.comwrote:
On May 30, 6:29 pm, Chris Dollin <chris.dol...@hp.comwrote:
Shraddha wrote:
What is mean by normalization of pointers...Where we use that?
We don't. There's no such concept in Standard C.
Tell us more about your problem.
--
"A facility for quotation covers the absence of original thought."/Gaudy Night/
Hewlett-Packard Limited registered no:
registered office: Cain Road, Bracknell, Berks RG12 1HN 690597 England

I read about it in the explanation of the far pointers...
there they say that -"The only difference between huge pointers and
far pointers is that...huge pointers are normalized..."

So I am asking what is far pointers?
far pointers are the ptrs which can point to adress beyond 64kb i.e.
the segment to which the pointer belong.

because of normalization huge ptrs at different give diffrent adress
so the huge ptr is not a used ptr.

Jun 1 '07 #30

P: n/a

"Chris Hills" <ch***@phaedsys.orgwrote in message
news:T6**************@phaedsys.demon.co.uk...
In fact numerous as PC's are they there are far more embedded systems.
These are not al 8 bit systems but 4-128 bits...... I was programming 64
bit embedded systems well over a decade ago.
But typically an embedded processor will run only one program in its useful
life.
--
Free games and programming goodies.
http://www.personal.leeds.ac.uk/~bgy1mm

Jun 1 '07 #31

P: n/a
Malcolm McLean wrote, On 01/06/07 23:47:
>
"Chris Hills" <ch***@phaedsys.orgwrote in message
news:T6**************@phaedsys.demon.co.uk...
>In fact numerous as PC's are they there are far more embedded systems.
These are not al 8 bit systems but 4-128 bits...... I was programming
64 bit embedded systems well over a decade ago.
But typically an embedded processor will run only one program in its
useful life.
What, you meant the web server, VPN client, VPN servers etc in my router
are all the same program? One that was not changed when I last upgraded
the firmware?

That is not to mention my TiVo on which I installed an FTP server, web
server and various other programs. Admittedly the TiVo is a bit unusual,
but my router/modem/wireless access point/VPN clients/VPN servers etc
all in the one device is not.
--
Flash Gordon
Jun 2 '07 #32

P: n/a
Flash Gordon wrote:
Malcolm McLean wrote, On 01/06/07 23:47:
>>
"Chris Hills" <ch***@phaedsys.orgwrote in message
news:T6**************@phaedsys.demon.co.uk...
>>In fact numerous as PC's are they there are far more embedded
systems. These are not al 8 bit systems but 4-128 bits...... I was
programming 64 bit embedded systems well over a decade ago.
But typically an embedded processor will run only one program in its
useful life.

What, you meant the web server, VPN client, VPN servers etc in my router
are all the same program? One that was not changed when I last upgraded
the firmware?
Considering the (tens of) millions of MCUs embedded in white goods, cars
and other deeply embedded applications, Malcolm's statement is probably
true.

--
Ian Collins.
Jun 2 '07 #33

P: n/a
In article <j_******************************@bt.com>, Malcolm McLean
<re*******@btinternet.comwrites
>
"Chris Hills" <ch***@phaedsys.orgwrote in message
news:T6**************@phaedsys.demon.co.uk...
>In fact numerous as PC's are they there are far more embedded
systems. These are not al 8 bit systems but 4-128 bits...... I was
programming 64 bit embedded systems well over a decade ago.
But typically an embedded processor will run only one program in its
useful life.
Generally yes but it is less true than it was.
--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

Jun 2 '07 #34

P: n/a
In article <5c*************@mid.individual.net>, Ian Collins
<ia******@hotmail.comwrites
>Flash Gordon wrote:
>Malcolm McLean wrote, On 01/06/07 23:47:
>>>
"Chris Hills" <ch***@phaedsys.orgwrote in message
news:T6**************@phaedsys.demon.co.uk...
In fact numerous as PC's are they there are far more embedded
systems. These are not al 8 bit systems but 4-128 bits...... I was
programming 64 bit embedded systems well over a decade ago.

But typically an embedded processor will run only one program in its
useful life.

What, you meant the web server, VPN client, VPN servers etc in my router
are all the same program? One that was not changed when I last upgraded
the firmware?
Considering the (tens of) millions of MCUs embedded in white goods, cars
and other deeply embedded applications, Malcolm's statement is probably
true.
I agree but apparently both my dishwasher and washing machine can be
firmware up-gradeble.... though that hasn't happened AKAIK in the 5
years since I bought them
--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

Jun 2 '07 #35

P: n/a
Chris Hills wrote, On 02/06/07 10:27:
In article <5c*************@mid.individual.net>, Ian Collins
<ia******@hotmail.comwrites
>Flash Gordon wrote:
>>Malcolm McLean wrote, On 01/06/07 23:47:

"Chris Hills" <ch***@phaedsys.orgwrote in message
news:T6**************@phaedsys.demon.co.uk...
In fact numerous as PC's are they there are far more embedded
systems. These are not al 8 bit systems but 4-128 bits...... I was
programming 64 bit embedded systems well over a decade ago.
>
But typically an embedded processor will run only one program in its
useful life.

What, you meant the web server, VPN client, VPN servers etc in my router
are all the same program? One that was not changed when I last upgraded
the firmware?
Considering the (tens of) millions of MCUs embedded in white goods, cars
and other deeply embedded applications, Malcolm's statement is probably
true.

I agree but apparently both my dishwasher and washing machine can be
firmware up-gradeble.... though that hasn't happened AKAIK in the 5
years since I bought them
It's a changing world. More and more things have web interfaces and/or
other things, someone even made a fridge with a web browser. Many are
upgradable. A number run versions of Linux. I know I have a lot of
embedded processors in my house that run multiple programs. Probably
most still only run one, although lots are upgradable (including in
cars) so that could easily change. It also depends on your definition of
program, my bread maker says it has several programs, so do my washing
machine and dish washer ;-)
--
Flash Gordon
Clutching at Linux based straws with web interfaces.
Jun 2 '07 #36

P: n/a
In article <pc************@news.flash-gordon.me.uk>, Flash Gordon
<sp**@flash-gordon.me.ukwrites
>Chris Hills wrote, On 02/06/07 10:27:
>In article <5c*************@mid.individual.net>, Ian Collins
<ia******@hotmail.comwrites
>>Flash Gordon wrote:
Malcolm McLean wrote, On 01/06/07 23:47:
>
"Chris Hills" <ch***@phaedsys.orgwrote in message
news:T6**************@phaedsys.demon.co.uk.. .
>In fact numerous as PC's are they there are far more embedded
>systems. These are not al 8 bit systems but 4-128 bits...... I was
>programming 64 bit embedded systems well over a decade ago.
>>
But typically an embedded processor will run only one program in its
useful life.

What, you meant the web server, VPN client, VPN servers etc in my router
are all the same program? One that was not changed when I last upgraded
the firmware?

Considering the (tens of) millions of MCUs embedded in white goods, cars
and other deeply embedded applications, Malcolm's statement is probably
true.
I agree but apparently both my dishwasher and washing machine can be
firmware up-gradeble.... though that hasn't happened AKAIK in the 5
years since I bought them

It's a changing world. More and more things have web interfaces and/or
other things,
Mine have rs232 interfaces more the technicians to reprogram. Not a
network interface.
someone even made a fridge with a web browser.
Most commercial chillers in supermarkets have tci/ip for system
monitoring.
>Many are upgradable.
Yes.
A number run versions of Linux.
This is irrelevant. There are many rtos (and none) in use. Most don't
use an rtos and linux is inappropriate for most
>I know I have a lot of embedded processors in my house that run
multiple programs. Probably most still only run one, although lots are
upgradable (including in cars) so that could easily change. It also
depends on your definition of program, my bread maker says it has
several programs, so do my washing machine and dish washer ;-)
:-)

--
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
\/\/\/\/\ Chris Hills Staffs England /\/\/\/\/
/\/\/ ch***@phaedsys.org www.phaedsys.org \/\/\
\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

Jun 3 '07 #37

This discussion thread is closed

Replies have been disabled for this discussion.