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POWhat is the explaination for this simple pointer program output
 

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  1. POWhat is the explaination for this simple pointer program output
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    <p>I tried to understand the size of address used to store variables and pointers, pointers-pointers and pointers-pointers-pointers. The results are kind of confusing. </p> <p>Here is the code:</p> <pre><code>#include &lt;stdio.h&gt; #include &lt;conio.h&gt; #include &lt;stdlib.h&gt; int main(void) { char *** ppptr_string = NULL; int *** ppptr_int = NULL; double *** ppptr_dbl = NULL; char c=0; int i=0; double d=0; printf("\n %d %d %d %d %d\n", sizeof(&amp;ppptr_string), sizeof(ppptr_string), sizeof(*ppptr_string), sizeof(**ppptr_string), sizeof(***ppptr_string)); printf("\n %d %d %d %d %d\n", sizeof(&amp;ppptr_int), sizeof(ppptr_int), sizeof(*ppptr_int), sizeof(**ppptr_int), sizeof(***ppptr_int)); printf("\n %d %d %d %d %d\n", sizeof(&amp;ppptr_dbl), sizeof(ppptr_dbl), sizeof(*ppptr_dbl), sizeof(**ppptr_dbl), sizeof(***ppptr_dbl)); printf("\n sizeof(char) = %d, sizeof(int) = %d, sizeof(double) = %d", sizeof(c), sizeof(i), sizeof(d)); printf("\n sizeof(&amp;char) = %d, sizeof(&amp;int) = %d, sizeof(&amp;double) = %d", sizeof(&amp;c), sizeof(&amp;i), sizeof(&amp;d)); getch(); return 0; } </code></pre> <p>Now the confusion. I can see that a variable address is always 2 bytes long on this machine. Regardless of type of the variable and regardless of the whether its a pointer variable. But why do I get size of 4 for so many entries in here? The pointer has size 4 always regardless of the type. The >address&lt; at which the variable is stored is of size 2. And the content pointed to has a sized depending on the type.</p> <p>Why do I get 4s in the output for sizeof??</p> <p>My output from Borland C++ 5.02 <img src="https://i.stack.imgur.com/uxKkM.png" alt="enter image description here"></p>
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    1. USquantum231
    1. USquantum231
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    1. COconio.h? Is this an MS-DOS compiler?
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      1. USsrc
    2. COplease provide ouput for I don't get when you see 4s and when 2s.
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      1. POWhat is the explaination for this simple pointer program output
      1. USKuba Wyrostek
    3. COIf you get 4 for the pointer sizes, that's beause those kinds of pointers are 4 bytes on your machine. The language standard doesn't say what size a pointer should be.
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      1. POWhat is the explaination for this simple pointer program output
      1. USBo Persson
 

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