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Re: rms from rosettacode

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jt@toerring.de (Jens Thoms Toerring) writes:

> Correct. And that's because you can't pass an array to a function,
> that's simply not possible in C. All you can pass to a function is
> a pointer to an element (typically the first) of an array (when you
> call a function with an array as an argument the array is silently
> converted to such a pointer to its first element). [...]

C99 didn't change any of these fundamentals, but it did make
passing multidimensional arrays to functions more convenient
using "variably modified parameters", which seem to be related to
this topic even if not an answer to the OP's question.

Here's the example from the standard itself:

    void addscalar(int n, int m, double a[n][n*m+300], double x);

    int main()
    {
        double b[4][308];
        addscalar(4, 2, b, 2.17);
        return 0;
    }

    void addscalar(int n, int m, double a[n][n*m+300], double x)
    {
        for (int i = 0; i < n; i++)
                 for (int j = 0, k = n*m+300; j < k; j++)
                           // a is a pointer to a VLA with n*m+300 elements
                           a[i][j] += x;
    }

-- 
"I should killfile you where you stand, worthless human." --Kaz

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rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-27 11:25 +0100
  Re: rms from rosettacode James Kuyper <jameskuyper@verizon.net> - 2011-12-27 06:48 -0500
    Re: rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-27 13:01 +0100
      Re: rms from rosettacode James Kuyper <jameskuyper@verizon.net> - 2011-12-27 07:10 -0500
        Re: rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-27 13:36 +0100
          Re: rms from rosettacode James Kuyper <jameskuyper@verizon.net> - 2011-12-27 10:04 -0500
    Re: rms from rosettacode Keith Thompson <kst-u@mib.org> - 2011-12-27 14:42 -0800
      Re: rms from rosettacode James Kuyper <jameskuyper@verizon.net> - 2011-12-27 18:46 -0500
  Re: rms from rosettacode 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-27 09:49 -0800
  Re: rms from rosettacode "BartC" <bc@freeuk.com> - 2011-12-27 18:14 +0000
    Re: rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-27 19:33 +0100
      Re: rms from rosettacode jt@toerring.de (Jens Thoms Toerring) - 2011-12-27 19:04 +0000
        Re: rms from rosettacode Keith Thompson <kst-u@mib.org> - 2011-12-27 14:45 -0800
        Re: rms from rosettacode blp@cs.stanford.edu (Ben Pfaff) - 2011-12-27 14:57 -0800
      Re: rms from rosettacode "BartC" <bc@freeuk.com> - 2011-12-27 19:06 +0000
        Re: rms from rosettacode Bull in a China Blue Shop <chine.bleu@yahoo.com> - 2011-12-27 16:16 -0800
      Re: rms from rosettacode James Kuyper <jameskuyper@verizon.net> - 2011-12-27 14:11 -0500
      Re: rms from rosettacode Seebs <usenet-nospam@seebs.net> - 2011-12-27 20:13 +0000
      Re: rms from rosettacode Johann Klammer <klammerr@NOSPAM.aon.at> - 2011-12-28 00:23 +0100
      Re: rms from rosettacode 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-27 15:54 -0800
        Re: rms from rosettacode Keith Thompson <kst-u@mib.org> - 2011-12-27 22:53 -0800
          Re: rms from rosettacode Seebs <usenet-nospam@seebs.net> - 2011-12-28 06:29 +0000
          Re: rms from rosettacode 88888 Dihedral <dihedral88888@googlemail.com> - 2011-12-28 02:45 -0800
  Re: rms from rosettacode Kaz Kylheku <kaz@kylheku.com> - 2011-12-27 19:53 +0000
    Re: rms from rosettacode Seebs <usenet-nospam@seebs.net> - 2011-12-27 20:13 +0000
    Re: rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-27 21:31 +0100
      Re: rms from rosettacode Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-12-27 20:49 -0500
        Re: rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-28 11:42 +0100
          Re: rms from rosettacode Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-12-29 08:18 -0800
        Re: rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-28 11:54 +0100
          Re: rms from rosettacode Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-12-29 04:12 +0200
            Re: rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-29 14:38 +0100
        Re: rms from rosettacode Nick Keighley <nick_keighley_nospam@hotmail.com> - 2011-12-28 02:26 -0800
          Re: rms from rosettacode Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-12-28 21:35 -0500
            Re: rms from rosettacode superpollo <superpollo@tznvy.pbz> - 2011-12-29 14:10 +0100
        Re: rms from rosettacode James Kuyper <jameskuyper@verizon.net> - 2011-12-28 08:03 -0500
          Re: rms from rosettacode "BartC" <bc@freeuk.com> - 2011-12-28 13:32 +0000
            Re: rms from rosettacode Dr Nick <3-nospam@temporary-address.org.uk> - 2011-12-28 13:41 +0000
            Re: rms from rosettacode Kaz Kylheku <kaz@kylheku.com> - 2011-12-28 19:29 +0000
            Re: rms from rosettacode Keith Thompson <kst-u@mib.org> - 2011-12-28 13:47 -0800
            Re: rms from rosettacode Phil Carmody <thefatphil_demunged@yahoo.co.uk> - 2011-12-29 04:19 +0200
      Re: rms from rosettacode Kaz Kylheku <kaz@kylheku.com> - 2011-12-28 19:11 +0000

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