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    <p>Pointers-to-pointers (hence pointers-to-arrays by proxy) are really useful. If you have a function/method and it takes a pointer-to-value argument you can change the value inside your function and that value stays in scope after you leave the function - pass-by-reference of course. However you can't change the address your pointer points at - e.g. make the pointer you passed into a NULL pointer, or point it at a different value somewhere else in memory. If you use a pointer-to-pointer-to-value then you can change the value of the 'middle' pointer inside your function. I think the MySQL C-connector library is an example of where this is used.</p> <p>In your example you could pass <code>ptrToAnOneDimArray</code> into a function and make *ptrToAnOneDimArray be a NULL pointer or a pointer to some other data rather than <code>intArrayOne</code> - as <code>intArrayOne</code> is a fixed size by the compiler (on the stack) then you could dynamically update *ptrToAnOneDimArray from the stack to be an array malloc()'d on the heap.</p> <pre><code>#include &lt;stdio.h&gt; #include &lt;stdlib.h&gt; #define SIZE 3 void display(char* data) { int i = 0; for(i=0 ; i&lt;SIZE ; i++) { printf("%c ", data[i]); } } void changeMyArgument(char** pointerToPointer) { *pointerToPointer = (char*) malloc(SIZE * sizeof(char)); /* now we use array notation for a change */ (*pointerToPointer)[0] = 'X'; (*pointerToPointer)[1] = 'Y'; (*pointerToPointer)[2] = 'Z'; } int main() { /* intArrayOne is implicitly char* */ char intArrayOne[SIZE] = {'A', 'B', 'C'}; char* arraysArePointers = intArrayOne; /* ptrToAnOneDimArray is implicitly char** */ char** ptrToAnOneDimArray; ptrToAnOneDimArray = &amp;arraysArePointers; display(*ptrToAnOneDimArray); changeMyArgument(ptrToAnOneDimArray); display(*ptrToAnOneDimArray); } </code></pre>
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    1. POWhy should we use pointer-to-arrays in C/C++?
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    1. COPlease provide some code as an example.
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    2. CO`you can't change the address your pointer points at` - that's curious
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    3. CO@Artur not if you pass the pointer *by value* into a function.
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