title: Error: expected declaration specifiers or '...' before XXX (all kinds of parameters)
body: <p>Just getting started with Linux learning. Ubuntu 18.04, linux-kernel 4.15 .
  Trying these simple code:</p>
  
  <p><a href="https://i.stack.imgur.com/q3lUj.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/q3lUj.png" alt="error"></a></p>
  
  <p>I supposed there's something wrong with stdio.h, but failed to figured it out. Expecting some help.</p>
  
  <pre><code>#include&lt;stdio.h&gt;
  
  char s[20];
  """
  unsigned long ul = 1234567890;
  sprintf(s,"%u",ul);
  s="asb";
  printf("%s\n",s);
  </code></pre>