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    <p>It looks like you are trying to create an array of <code>struct myStruct</code>s. There are a few ways to do so. The first is to allocate the structs on your stack ala:</p> <pre><code>struct myStruct p[N]; </code></pre> <p>where <code>N</code> is some positive integer value. Note that by declaring this array on the stack, once your program leaves the scope of wherever this array was declared in, the array and all its contents become lost. Example:</p> <pre><code>struct myStruct foo(int N) { int i; struct myStruct p[N]; for(i = 0; i &lt; N; i++) p[i].intVar = i; for(i = 0; i &lt; N; i++) //Prints value of intVar of each struct myStruct on a different line printf("%d\n", p[i].intVar); // Returns p but the moment the scope returns to the main function, p // ceases to exist return p; } int main() { struct myStruct p[10] = foo(10); // This gives you an error as the program has no notion of p outside the scope // of foo printf("%d\n", p[5].intVar); } </code></pre> <p>The other option is to allocate the array onto the heap ala:</p> <pre><code>struct myStruct **p = malloc(N * sizeof(struct myStruct *)); </code></pre> <p>Note that constructing an array like this means you have to also allocate space on the heap for each struct in the array. Example:</p> <pre><code>struct myStruct** foo(int N) { struct myStruct **p = malloc(N * sizeof(struct myStruct *)); int i; for(i = 0; i &lt; N; i++) p[i] = malloc(sizeof(struct myStruct)); return p; } int main() { struct myStruct **p = foo(10); p[5]-&gt;intVar = 10; // This is now valid because p and its elements // exist on the heap until you free them printf("%d\n", p[5]-&gt;intVar); // For every malloc you must have a free, lest // you run into memory leaks int i; for(i = 0; i &lt; 10; i++) free(p[i]); free(p); } </code></pre>
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    1. CO`sizeof *p` will be the same as `sizeof(struct myStruct)` because the type of `*p` **is** `struct myStruct`. The type of `p` is a pointer type, and therefore `sizeof p` will be the size of a pointer type.
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    2. COAlso, it has been said countless times before, [you shouldn't cast the result of `malloc`](http://stackoverflow.com/questions/605845/do-i-cast-the-result-of-malloc).
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    3. CO@Dreamlax is right please disregard my answer. It seems to me you might be trying to allocate an array of `struct myStruct`s?
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