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    <p>-You need to use double pointer since you need to change the pointer to your struct and call by reference is not allowed in C.</p> <p>-It would not work with a single pointer. Because you want to change the pointer to your object. You do it by the statement <code>*currItem = (*currItem)-&gt;next;</code> In order to change it permanently, you need to use a pointer to it. Which makes you use double pointer.</p> <p>Think of it that way:</p> <p>you have an integer variable <code>a</code> that you want a function to change its value. You simply call this function with a pointer to the variable <code>a</code> like:</p> <pre><code>void changeTheValue(int *x) { *x = 7; } void main() { int a = 5; changeTheValue(&amp;a); } </code></pre> <p>and in your case you want to change your <em>pointer's</em> value and you simply pass its pointer to the function.(double pointer) simple as that. <strong>If you want to change value of something with a function, then you have to pass its pointer to the function.</strong></p> <p>-When you make a call to malloc, you want space from it. And you state that you want a space as big as the size of your struct. (Like when you did in here <code>list = (struct item*) malloc(sizeof(struct item));</code>) and malloc allocates a space as big as your struct. If size of your struct is 1 byte then you have a 1 byte space, if it is 4, then you have consecutive 4 bytes. See, this is how your struct is kept in the memory. If you declare a struct variable or an array etc. then your struct is kept in memory like (dunno if it is a good metaphor) an array. The first member comes first, and then the second...</p> <p>say if you have a struct</p> <pre><code>struct myStruct { int a; float b; char c; }; </code></pre> <p>then the memory looks like</p> <hr> <p>a</p> <hr> <p>b</p> <hr> <p>c</p> <p>ps: you are making an illegal call to free on the line <code>free(intTemp);</code> you are *free*ing a variable that you didn't *malloc*ed.</p>
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