title: Why does scanf returns control back to the program on pressing Enter key?
body: <p>I wrote the following program.</p>
  
  <pre><code>void main()
  {
     int   *piarrNumber1   = (int *) calloc(1, sizeof(int));
     int   iUserInput      = 0;
  
     scanf("%d", &amp;iUserInput);
     piarrNumber1[(sizeof piarrNumber1 / sizeof(int)) - 1] = iUserInput;
     printf("\n%d\n", piarrNumber1[0]);
  }
  </code></pre>
  
  <p>I input "3" followed by a TAB from the keyboard. Nothing happens. Then, I press Enter Key. I get "3" printed and the program ends.</p>
  
  <p>If "TAB" [Horizanotal Tab] and "Enter" [Newline] are both whitespace characters, why is their behaviour different?</p>