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copied!<p>What you are looking exists in C++, but not in C, I believe. In C++ you can define template functions for working with arrays of size, known at a compile time, and compiler takes care of the rest. In C, there are two approaches:</p> <ul> <li><p>Define the size explicitly<br> This is the case of functions like <code>memcpy</code>, where you specify number of elements </p> <pre><code>void process_array(int *data[], size_t max_x, size_t max_y) .... </code></pre></li> <li><p>Define the size using invalid number<br> This is the case of functions like <code>strlen</code> where data is terminated by certain value (<code>'\0'</code> here)<br> So if you want to have a function with matrix, but variable number of elements, you must define a way how to indicate that in the data.</p> <pre><code>#define ARRAY_TERM -1 void process_array(int *data[]) { size_t i, j; for (i = 0; data[i]; i++) { for (j = 0; data[i][j] != ARRAY_TERM; j++) { ... } } } ... </code></pre></li> </ul> <p>Hope you've got the idea. Not very convenient to use.</p> <p>There is another approach: define your own type. Yes, it is a viable option in many cases:</p> <pre><code>typedef struct array *array_t; struct array { size_t max_x, max_y; int *data; }; </code></pre> <p>Basic set of functions to work with it:</p> <pre><code>int array_init(array_t *a; size_t max_x, size_t max_y) { array_t res; res = malloc(sizeof(*res)); res->max_x = max_x; res->max_y = max_y; res->data = calloc(max_x * max_y, sizeof(int)); *a = res; return 0; } void array_destroy(array_t *a) { free((*a)->data); free(*a); } </code></pre> <p>And then you can define your additional functions for operation.</p>

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