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copied!<p>The warning is exactly right. Your function wants an array of pointers. You're giving it an array of arrays.</p> <p>Expected:</p> <pre> sep_foo: +------+ +-----+ |char**|--> 0: |char*|-->"string1" +------+ +-----+ 1: |char*|-->"string2" +-----+ *sep_foo_qty-1: |... | +-----+ </pre> <p>What you provided:</p> <pre> sep_foo: +--------------------------------+ 0: | char[MAX_STRING_LENGTH] | +--------------------------------+ 1: | char[MAX_STRING_LENGTH] | +--------------------------------+ MAX_QTY-1: | ... | +--------------------------------+ </pre> <p>An array with elements of type <code>X</code> can "decay" into a pointer-to-<code>X</code>, or <code>X*</code>. But the value of <code>X</code> isn't allowed to change in that conversion. Only <em>one</em> decay operation is allowed. You'd need it to happen twice. In your case, <code>X</code> is array-of-<code>MAX_STRING_LENGTH</code>-chars. The function wants <code>X</code> to be pointer-to-char. Since those aren't the same, the compiler warns you. I'm a bit surprised it was just a warning since nothing good can come from what the compiler allowed to happen.</p> <p>In your function, you could write this code:</p> <pre><code>char* y = NULL; *sep_foo = y; </code></pre> <p>That's legal code since <code>sep_foo</code> is a <code>char**</code>, so <code>*sep_foo</code> is a <code>char*</code>, and so is <code>y</code>; you can assign them. But with what you tried to do, <code>*sep_foo</code> wouldn't <em>really</em> be a <code>char*</code>; it would be pointing to an array of char. Your code, in effect, would be attempting to do this:</p> <pre><code>char destination[MAX_STRING_LENGTH]; char* y = NULL; destination = y; </code></pre> <p>You can't assign a pointer into an array, and so the compiler warns that the call is no good.</p> <p>There are two ways to solve this:</p> <ul> <li><p>Change the way you declare and allocate <code>sep_foo</code> on the calling side so it matches what the function expects to receive:</p> <pre><code>char** sep_foo = calloc(MAX_QTY, sizeof(char*)); for (int i = 0; i < MAX_QTY; ++i) sep_foo[i] = malloc(MAX_STRING_LENGTH); </code></pre> <p>or, equivalently</p> <pre><code>char* sep_foo[MAX_QTY]; for (int i = 0; i < MAX_QTY; ++i) sep_foo[i] = malloc(MAX_STRING_LENGTH); </code></pre></li> <li><p>Change the prototype of the function to accept what you're really giving it:</p> <pre><code>int parse(const char *foo, char sep_foo[MAX_QTY][MAX_STRING_LENGTH], int *sep_foo_qty); </code></pre></li> </ul>

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