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Re: Arrays Vs Pointers

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在 2012年2月9日星期四UTC+8下午4时20分23秒，Nick Keighley写道：
> On Feb 7, 9:28 pm, peter 
>  wrote:
> 
> > I am currently exploring the world of pointers and have encounter some
> > inconsistent information regarding the best way to reference an
> > array: array[1]   OR    *(array +1).
> 
> which is shortest and clearest? I'm much more of a fan of array
> notation. Simple, clear and less typing. Modern compilers (anything in
> the last 20 years or so) generate identical code anyway.
> 
> The only time I tend to use pointers is say picking a comms packet
> apart.
> 
>    pkt_ptr = &packet [0];
>    type = *pkt_ptr++;
>    length = (*pkt_ptr) * 256 + *pkt_ptr;
>    pkt_ptr += 2;
> 
> Each time you read a byte you advance the pointer you don't have to
> keep track and count bytes yourself. So is the CRC field in byte 21 or
> byte 22? Well it depends if the Qualifier option was selected.
> 
> > One book says that you should not use the syntax array[1] because
> > of performance reason.
> 
> bad reason. It likely makes no difference.
> 
> 1. write clear, correct code
> 2. test it thoughly
> 3. if its too slow make it faster
> 
> step 3 is not necessary far more often tahn many people imagine.
> People often *start* at step 3. "wow that's /really/ fast, all you
> have to do now is make it give the right answer!"
> 
> > Another book says that the syntax array[1] is
> > only used by FORTRAN programmers who do not understand c pointers.
> 
> burn the book.
> 
> blacklist the place you bought it
>
Don't burn the book. That is not the way to learn black magics in manny
books in the sophomore or above levels. 
 
 
> tell your friends
> 
> hell, tell us! What was this book?
> 
> > So
> > what is the true oh wizards? Does it make a difference?
> 
> WRITE SIMPLE CODE

Learn to write  more black spells in the graduate school levels. 
Don't be so innocent like a child in the elementary school.

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Arrays Vs Pointers peter <pc722@nospam.mail.com.br> - 2012-02-07 21:28 +0000
  Re: Arrays Vs Pointers William Ahern <william@wilbur.25thandClement.com> - 2012-02-07 13:50 -0800
  Re: Arrays Vs Pointers James Kuyper <jameskuyper@verizon.net> - 2012-02-07 17:13 -0500
  Re: Arrays Vs Pointers Stephen Sprunk <stephen@sprunk.org> - 2012-02-07 16:38 -0600
    Re: Arrays Vs Pointers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-07 23:09 +0000
  Re: Arrays Vs Pointers Keith Thompson <kst-u@mib.org> - 2012-02-07 14:41 -0800
    Re: Arrays Vs Pointers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-07 23:07 +0000
      Re: Arrays Vs Pointers James Kuyper <jameskuyper@verizon.net> - 2012-02-07 19:14 -0500
    Re: Arrays Vs Pointers Shao Miller <sha0.miller@gmail.com> - 2012-02-07 18:21 -0500
      Re: Arrays Vs Pointers Keith Thompson <kst-u@mib.org> - 2012-02-07 16:25 -0800
        Re: Arrays Vs Pointers Shao Miller <sha0.miller@gmail.com> - 2012-02-07 20:31 -0500
    Re: Arrays Vs Pointers Ike Naar <ike@sverige.freeshell.org> - 2012-02-07 23:36 +0000
      Re: Arrays Vs Pointers Keith Thompson <kst-u@mib.org> - 2012-02-07 16:26 -0800
    Re: Arrays Vs Pointers Keith Thompson <kst-u@mib.org> - 2012-02-07 16:24 -0800
  Re: Arrays Vs Pointers Paul N <gw7rib@aol.com> - 2012-02-07 14:55 -0800
  Re: Arrays Vs Pointers Shao Miller <sha0.miller@gmail.com> - 2012-02-07 18:11 -0500
  Re: Arrays Vs Pointers John Bode <jfbode1029@gmail.com> - 2012-02-08 16:06 -0800
    Re: Arrays Vs Pointers Philip Lantz <prl@canterey.us> - 2012-02-08 23:25 -0800
      Re: Arrays Vs Pointers John Bode <jfbode1029@gmail.com> - 2012-02-09 05:34 -0800
        Re: Arrays Vs Pointers Philip Lantz <prl@canterey.us> - 2012-02-10 01:04 -0800
  Re: Arrays Vs Pointers Nick Keighley <nick_keighley_nospam@hotmail.com> - 2012-02-09 00:20 -0800
    Re: Arrays Vs Pointers 88888 Dihedral <dihedral88888@googlemail.com> - 2012-02-09 23:42 -0800
    Re: Arrays Vs Pointers gwowen <gwowen@gmail.com> - 2012-02-10 01:20 -0800
    Re: Arrays Vs Pointers David Thompson <dave.thompson2@verizon.net> - 2012-02-18 23:12 -0500
      Re: Arrays Vs Pointers Kaz Kylheku <kaz@kylheku.com> - 2012-02-19 05:53 +0000
        Re: Arrays Vs Pointers Markus Wichmann <nullplan@gmx.net> - 2012-02-19 18:54 +0100
          Re: Arrays Vs Pointers Willem <willem@toad.stack.nl> - 2012-02-19 18:51 +0000
          Re: Arrays Vs Pointers "io_x" <a@b.c.invalid> - 2012-02-19 21:29 +0100
          Re: Arrays Vs Pointers Markus Wichmann <nullplan@gmx.net> - 2012-02-20 11:24 +0100
          Re: Arrays Vs Pointers gwowen <gwowen@gmail.com> - 2012-02-21 01:51 -0800
  Re: Arrays Vs Pointers Willem <willem@toad.stack.nl> - 2012-02-19 12:32 +0000
    Re: Arrays Vs Pointers Keith Thompson <kst-u@mib.org> - 2012-02-19 12:21 -0800
      Re: Arrays Vs Pointers Willem <willem@toad.stack.nl> - 2012-02-19 21:00 +0000
        Re: Arrays Vs Pointers Ben Bacarisse <ben.usenet@bsb.me.uk> - 2012-02-19 21:42 +0000
      Re: Arrays Vs Pointers pete <pfiland@mindspring.com> - 2012-02-20 17:32 -0500
        Re: Arrays Vs Pointers James Kuyper <jameskuyper@verizon.net> - 2012-02-20 17:56 -0500
        Re: Arrays Vs Pointers Keith Thompson <kst-u@mib.org> - 2012-02-20 15:19 -0800
          Re: Arrays Vs Pointers Keith Thompson <kst-u@mib.org> - 2012-02-20 16:35 -0800
            Re: Arrays Vs Pointers pete <pfiland@mindspring.com> - 2012-02-20 22:53 -0500
              Re: Arrays Vs Pointers Keith Thompson <kst-u@mib.org> - 2012-02-20 21:16 -0800
            Re: Arrays Vs Pointers Richard Sanders <lnr729@gmail.com> - 2012-02-21 00:26 -0800
              Re: Arrays Vs Pointers pete <pfiland@mindspring.com> - 2012-02-21 11:46 -0500

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