Comments

• Comments are started with `/*' (slash immediately followed by asterisk) and ended with `*/' (asterisk followed by slash)
• comments can contain anything except the comment-ending `*/'
  • /* good comment */
  • / * * / is not a valid comment (because of the whitespace between the `/' and the `*')
  • /* can even contain another /* */
  • /* including "*/" */ is an error
    • compiler sees comment as `/* including "*/' then tried to compile `" */'
• Comments may even span multiple lines:

  	/*
  	 * Good for setting comments off
  	 * from the rest of your code
  	 */
  

  • need to be careful because of this

    	a = 1;	/* forgot comment terminator
    	a = 2;	/* everything ignored to here --> */
    	b = a;
    

    causes b to be set to 1
• Comments should not be used for disabling blocks of code
  • block of code could potentially contain an unnoticed comment

    	/* disabling block */
    	/*
    	  code
    	  ...
    	  code		/* unnoticed comment */
    	  ...
    	  code
    	*/
    

    would cause the embedded */ to end the comment, and everything after it to get compiled (possibly unnoticed)
  • a better way to disable a chunk of code is

    	#ifdef 0
    	  code
    	  ...
    	  code		/* unnoticed comment */
    	  ...
    	  code
    	#endif