title: My linux's gcc compiler not supporting boolean values
body: <p>I'm trying to make a function with return type as boolean...the syntax of the program seems to be correct but the compiler is giving errors....</p>
  
  <p>The header files I've included are:</p>
  
  <pre><code>#include&lt;stdio.h&gt;
  #include&lt;stdlib.h&gt;
  </code></pre>
  
  <p>the function I've created is:</p>
  
  <pre><code>34.bool checknull(struct node* node){
  35.    if ( node != NULL )
  36.        return TRUE;
  37.       
  38.    return false;
  39.}
  </code></pre>
  
  <p>and what I'm getting at compile time is</p>
  
  <pre><code>bininsertion.c:34:1: error: unknown type name ‘bool’
  bininsertion.c: In function ‘checknull’:
  bininsertion.c:36:10: error: ‘TRUE’ undeclared (first use in this function)
  bininsertion.c:36:10: note: each undeclared identifier is reported only once for each  function it appears in
  bininsertion.c:38:9: error: ‘false’ undeclared (first use in this function)
  </code></pre>
  
  <p>I've tried "TRUE,false" both in small and capital letters but doesn't seem to work...</p>