Accessing consecutively named arrays in C

asker Guest #2584727
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This may be a long shot, but anyway...

Say I have lots of arrays named list1[], list2[], list3[], etc.

I want a while() loop where I do something like this:

while(1)
{
   afunction(listX);
}


....where X is incremented each time.

In case you wonder why I want to do this, I'm saving C arrays from 
Wireshark to feed into C code for testing and the arrays it generates 
have incrementing numbers.  Typing in all these array names manually is 
tiring.
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Mark B. #2584763
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You could use a two-dimensional array, like so:


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#include <stdio.h>

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#define LIST_ELEM_MAX 4

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#define NO_OF_LIST    3

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int main()

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{

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  unsigned int i, j;

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  unsigned int lists[NO_OF_LIST][LIST_ELEM_MAX] = { { 1,  2,  3,  4 },

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                                                    { 2,  4,  6,  8 },

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                                                    { 5, 10, 15, 20 } };

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  for (i=0; i < NO_OF_LIST; i++)

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  {

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    for (j=0; j < LIST_ELEM_MAX; j++)

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    {

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      printf("Element %d of list %d: %d\n", j, i, lists[i][j]);

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    }

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    printf("\n");

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  }

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  return 0;

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}
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asker Guest #2584776
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Thanks for the reply, but that still means I have to change dozens or 
maybe hundreds of arrays that I simply cut and paste out of Wireshark.

If I could put some syntax around the entire block of arrays without 
having to change the syntax of each one, that would be better.
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gcc-help@gcc.gnu.org Guest #2585945
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You can do it like so:
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extern type_t list1[];

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extern type_t list2[];

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extern type_t list3[];

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type_t *lists[] =

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{

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    list1,

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    list2,

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    list3

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};

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extern void do_list (type_t*);

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void do_lists (void)

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{

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    size_t l;

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    for (l = 0; l < sizeof (lists) / sizeof (*lists); l++)

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        do_list (lists[l]);

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}
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asker Guest #2586239
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I ended up writing a simple C program to generate a very long list of 
function calls with incrementing array names being passed to the 
function.  It's messy, but it's the easiest thing I've come up with.
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